Month: October 2019

What is domain constraints in database?

Domain Constraints are user-defined columns that help the user to enter the value according to the data type. And if it encounters a wrong input it gives the message to the user that the column is not fulfilled properly.

What is a domain constraints give an example?

A domain is a unique set of values permitted for an attribute in a table. For example, a domain of month-of-year can accept January, February…. December as possible values, a domain of integers can accept whole numbers that are negative, positive and zero.

What is domain key constraint?

A domain constraint specifies the permissible values for a given attribute, while a key constraint specifies the attributes that uniquely identify a row in a given table.

What are 5 types of constraints?

An informational constraint is an attribute of a certain type of constraint, but one that is not enforced by the database manager.

• NOT NULL constraints.
• Unique constraints.
• Primary key constraints.
• (Table) Check constraints.
• Foreign key (referential) constraints.
• Informational constraints.

What are common uses of domain constraints?

Domain constraints are the most elementary form of integrity constraints. Domain constraints are used to constrain the value of a single column. They are used to test values inserted into the database and to test queries to make sure that a comparison is valid.

What is domain in relational database?

Each column of a relational table is defined on a domain. A domain is a set of values. A datatype, which is also defined for each column, consists of a domain of values and a set of operations on those values.

What are three major types of constraints?

The three primary constraints that project managers should be familiar with are time, scope, and cost. These are frequently known as the triple constraints or the project management triangle.

What are the three database constraints?

Data integrity is normally enforced in a database system by a series of integrity constraints or rules. Three types of integrity constraints are an inherent part of the relational data model: entity integrity, referential integrity and domain integrity.

What is an attribute domain in database?

Attribute domains are rules that describe the legal values of a field type. They are used to constrain the values allowed in any particular attribute for a table or feature class. They provide a method for enforcing data integrity by limiting what can be placed on a field to a valid list or range of choices.

Which of the following are domain constraints?

Domain constraints Domain constraints can be defined as the definition of a valid set of values for an attribute. The data type of domain includes string, character, integer, time, date, currency, etc. The value of the attribute must be available in the corresponding domain.

What are the 6 constraints?

To remember the Six Constraints, think “CRaB QueST” (Cost, Risk, Benefits, Quality, Scope and Time).

What are the four types of constraints?

Every project has to manage four basic constraints: scope, schedule, budget and quality. The success of a project depends on the skills and knowledge of the project manager to take into consideration all these constraints and develop the plans and processes to keep them in balance.

What is domain constraint?

Definition: Domain constraints are user defined data type and we can define them like this: Domain Constraint = data type + Constraints (NOT NULL / UNIQUE / PRIMARY KEY / FOREIGN KEY / CHECK / DEFAULT)

What are database constraints?

Database Constraints • Database constraints provide a way to guarantee that: – rows in a table have valid primary or unique key values – rows in a dependent table have valid foreign key values that reference rows in a parent table – individual column values are valid Did you try ⇒ www.HelpWriting.net ⇐?.

What are the key constraints of primary key in SQL?

Key constraints: PRIMARY KEY: Primary key uniquely identifies each record in a table. It must have unique values and cannot contain nulls. In the below example the ROLL_NO field is marked as primary key, that means the ROLL_NO field cannot have duplicate and null values.

What are foreign key constraints in UDB 400?

Foreign Key Constraints • A foreign key constraint specifies how records in different tables are related and how UDB/400 should handle row insert, delete, and update operations that might violate the relationship. • For example, sales rows are generally related to the customers who place the orders.

What should I avoid in Chicago?

What Not to Do in Chicago on Your 1st Visit

• Eating only deep-dish pizza.
• Skipping Wrigley Field.
• Putting ketchup on your hot dog.
• Shopping only on Michigan Avenue.
• Focusing on Navy Pier.
• Saying that the NYC skyline is better.
• Thinking only the Willis Tower Skydeck has incredible views.
• Renting a automobile in Chicago.

What is the coolest thing in Chicago?

Top Attractions in Chicago

1. The Art Institute of Chicago. 24,193. Art Museums.
2. Museum of Science and Industry. 11,048. Science Museums.
3. 360 Chicago Observation Deck. 10,911.
4. Cloud Gate. 18,100.
5. Millennium Park. 24,790.
6. Field Museum. 8,760.
7. Wrigley Field. 9,837.
8. The Magnificent Mile. 15,699.

What should you not miss when visiting Chicago?

10 Things Not to Miss in Chicago: a Beginner’s Guide

• Check Out a Show at “The Second City”
• Eat in the West Loop.
• Go Window Shopping on Michigan Avenue.
• Admire the 100-ton Bean Sculpture.
• Grab a Drink at the “Old Town Ale House”
• Head up to the 95th Floor of the John Hancock Center.
• Ride the Iconic Navy Pier Ferris Wheel.

Do and don’ts in Chicago?

Here are some of their major do’s and don’ts for enjoying all that the city has to offer:

• DON’T: Stay in one part of the city.
• INSTEAD: Leave the Loop and spend some time in Chinatown.
• DON’T: Spend an entire day at Navy Pier.
• INSTEAD: Visit some of the city’s museums.
• DON’T: Drive yourself around the city.

Is Chicago worth visiting?

You might live for wining and dining at famed restaurants; visiting world-renowned museums; meandering along jaw-dropping waterfronts; hearing ground-breaking music; watching award-winning theatrical productions; wiling away the hours in over 300 parks, visiting countless iconic buildings designed by some of the …

Is Chicago a safe city?

In terms of crime, Chicago is rated only 8% safer than other US cities. 1 out of 105 people is likely to become a victim of violent crime in Chicago. The further south or west you go, you are more likely to become a target of mugging.

What is Chicago known for?

What is Chicago Most Famous For?

• Millenium Park.
• Navy Pier.
• Chicago Riverwalk.
• Adler Planetarium.
• Magnificent Mile.
• Shedd Aquarium.
• Skydeck Chicago.
• Field Museum.

What is Chicago most known for?

Some of the many things Chicago is famous for are: Chicago-style hot dogs, Chicago-style (deep dish) pizza, Maxwell Street Polish Sausage, jazz music, and 1920s gangsters, for example Al Capone. Chicago is also known for architecture, for example the Sears Tower and museums. It is also known for its loyal sports fans.

What food is Chicago known for?

While Chicago is famous for tons of delicious food, 10 iconic food staples should top every diner’s must-try list.

• Deep-Dish Pizza. You can’t talk about iconic Chicago cuisine without including deep-dish pizza.
• Chicago Barbecue.
• Jibarito Sandwich.
• Steak.
• The Rainbow Cone.
• Pizza Puffs.
• Flaming Saganaki.
• Italian Beef Sandwich.

How unsafe is Chicago?

YES, according to statistics, Chicago is one of the most dangerous cities in the United States. According to, Wikipedia , Chicago’s overall crime rate, especially for violent crime, is higher than the US city average. In addition, Chicago’s crime level continues to rise.

Is Chicago Safe?

Chicago is a safe city for tourists to visit and is an amazing city with a lot to offer. There are world-class museums, restaurants, and nightlife options. The city is also very accessible, with a great public transportation system. With that said, go ahead and enjoy everything that Chicago has to offer.

Why do tourists go to Chicago?

What are some cool things to do in Chicago?

A lush green oasis in the middle of Chicago. A giant bronze coil of feces is both a tribute to doggie defecation and a reminder to pick it up. A speakeasy takes on Chicago’s drinking culture. Want to see fewer ads?

What is the most unusual attraction in Chicago?

Unusual Attractions in Chicago. Oz Park. This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood. Tiffany Dome. Woolly Mammoth Antiques and Oddities. Wicker Park Secret Agent Supply Co. Willis Tower Glass Platform.

Is there a Wizard of Oz Park in Chicago?

Names after L. Frank Baum, author of The Wonderful Wizard of Oz, this parkis located in Chicago’s Lincoln Park neighborhood. It ranks as one of the best unique things to do in Chicago thanks to its impressive statues of Oz characters such as Dorothy, Tin Man, Scarecrow, and Cowardly Lion.

Did you know Chicago has a French market?

It’s no secret Chicago has a thriving culinary scene. But, you might not know about the city’s French Market. With over 30 vendors, including those featuring French ingredients and dining-in options. As well as food on the go, this market is an ideal place to indulge in French cuisine. Conveniently, Chicago’s French Market is open Monday-Saturday.

Can you use a standard mattress in an RV?

Can You Put A Regular Mattress In An RV? You can put a regular mattress in an RV if the bed size or sleeping platform matches your mattress size. If it’s the right size, you can easily use a standard home mattress size in your camper or even a regular queen size, depending on the dimensions of your particular setup.

Is an RV mattress the same as a regular mattress?

RV mattress sizes are not the same as standard (or residential) mattress sizes. RV mattresses are often shorter or narrower than standard mattress sizes to accommodate the diverse spaces in a recreational vehicle. There is no universal height or thickness for each mattress size.

What are standard RV mattress sizes?

60″ x 80″
The RV Queen mattress size is one of the most commonly used beds in camping trucks and vans. It comes with three different dimensions; a short queen RV bed measuring about 60″ x 75″, a three-quarter queen bed measuring 48″ x 75″, and a standard queen measuring 60″ x 80″.

How thick is a standard RV mattress?

about 5 to 6 inches thick
RVs and campers usually come with foam mattresses, which are about 5 to 6 inches thick, and are not as comfortable as your home mattresses.

Can I put a regular queen mattress in my RV?

So, for those RVs, the mattress must be a custom “RV” size or it will hang over the edges of the bed platform. For instance, a standard Queen mattress is 60” x 80” while an RV Queen is the same width but is a bit shorter at 60” x 75”.

What size mattress is in a travel trailer?

RV Mattress Sizes Chart

Size	Dimensions
RV Olympic Queen	66″ x 80″
RV Queen	60″ x 80″
RV Short Queen	60″ x 75″ 60″ x 74″
RV Full	55″ x 75″ 54″ x 75″ 53″ x 75″

How are RV mattresses measured?

Measure your bed from the top to the bottom. This will determine the length of mattress that you will require for your RV bed. Measure from the top surface of the mattress area, vertically downward to what the mattress will be laying on. This will determine the depth (or height) of the mattress.

What is the difference between a queen mattress and a RV queen mattress?

Standard queen beds at home measures 60x80x11. An RV queen mattress on the other hand, is a few inches shorter at 60x75x11 (sometimes, 60×74 or shorter). It is sometimes referred to as “short queen” or “RV queen” by the happy camper communties.

What is the size of a queen mattress in an RV?

RV Mattress Sizes Chart

Size	Dimensions
RV King	76″ x 80″ 72″ x 80″ 72″ x 75″
RV Olympic Queen	66″ x 80″
RV Queen	60″ x 80″
RV Short Queen	60″ x 75″ 60″ x 74″

What are the dimensions of a RV king mattress?

What is the size of a RV King size mattress? There are two King sized RV mattresses. The RV King measures 72”x 80” while the RV Short King is five inches shorter at 72” x 75”.

What are the dimensions of a king size RV mattress?

RV Mattress Sizes Chart

Mattress Size	Dimensions (IN)	Dimensions (CM)
RV California King	72 inches by 84 inches	182.8 cm by 213.3 cm
RV King	72 inches by 80 inches	182.8 cm by 203.2 cm
RV Short King	72 inches by 75 inches	182.8 cm by 190.5 cm
Eastern King	76 inches by 80 inches	193.0 cm by 203.2 cm

What is the difference between an RV queen and a regular queen mattress?

For instance, a standard Queen mattress is 60” x 80” while an RV Queen is the same width but is a bit shorter at 60” x 75”. Likewise, a King mattress is 76” x 80” whereas an RV King mattress is a little narrower at 72” x 80”.

What kind of RV is a C25?

C25 Standard RV. Our medium size vehicle, the C25, has been a stalwart of fleet design for many years. With a rear corner double bed as well as a double bed over the cab it is ideal for two couples or a family of up to five.

What are the most common RV mattress sizes?

Here are the most common sizes: You’ll often find the RV king mattress in the larger RVs and campers, due to the size of the mattress. Standard RV king beds typically measure 72×80 inches, and may have radius corners at the foot of the bed.

What is an RV contouring mattress?

Contouring: How well a mattress conforms to the shape of the body determines how much pressure relief it provides. For RV owners who are active, a contouring mattress can relieve aches and pains from hiking and other activities. It can also reduce tension for those who have been driving for long periods of time.

What makes an RV mattress so comfortable?

Many RV mattresses are made with memory foam, which cushions the shoulders and hips to help keep the spine aligned. Noise: An RV is often a shared space for families who want to prevent sleep disturbances throughout the night.

Where are the 7 super volcanoes located?

There are many supervolcanoes around the world other than Yellowstone, including California’s Long Valley, Japan’s Aira Caldera, Indonesia’s Toba, and New Zealand’s Taupo. This latter supervolcano is the last to have ever released a super-eruption, which burst free some 26,500 years ago.

Where are the 12 super volcanoes located?

Known super eruptions

Name	Zone	Location
McMullen Supereruption	Yellowstone hotspot	Southern Idaho, United States
Heise Volcanic Field	Yellowstone hotspot	Idaho, United States
Cerro Guacha	Altiplano-Puna volcanic complex	Sur Lípez, Bolivia
Mangakino Caldera	Taupō Volcanic Zone	North Island, New Zealand

Where are the 3 super volcanoes located?

The United States is home to three active supervolcanoes, the USGS has determined: The famous Yellowstone, Long Valley and the Valles Caldera in New Mexico.

What are the 5 supervolcanoes?

1 – La Garita Caldera.

2 – Lake Toba.

3 – Cerro Guacha.

4 – Yellowstone Caldera.

5 – Lake Taupo.

6 – Cerro Galán.

7 – Island Park Caldera.

8 – Vilama.

Where are the 5 super volcanoes located?

Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand.

Where is the world’s largest super volcano?

The Yellowstone Caldera, sometimes referred to as the Yellowstone Supervolcano, is a volcanic caldera and supervolcano in Yellowstone National Park in the Western United States. The caldera and most of the park are located in the northwest corner of Wyoming.

What are the 3 super volcanoes?

What are the 2 super volcanoes?

Is Mount Etna A supervolcano?

Mount Etna consists of two edifices: an ancient shield volcano at its base, and the younger Mongibello stratovolcano, which was built on top of the shield. The basaltic shield volcano eruptions began about 500,000 years ago, while the stratovolcano began forming about 35,000 years ago from more trachytic lavas.

What is the biggest supervolcano on Earth?

the Yellowstone supervolcano
Seismologists have discovered a massive magma reservoir beneath the Yellowstone supervolcano in Wyoming, US, that suggests its volcanic system could be more than 5.6 times larger than was previously thought.

Where is Yellowstone Caldera located?

northwestern Wyoming
Yellowstone Caldera, enormous crater in the western-central portion of Yellowstone National Park, northwestern Wyoming, that was formed by a cataclysmic volcanic eruption some 640,000 years ago. It measures approximately 30 by 45 miles (50 by 70 km), covering a large area of the park.

What is a supervolcano BBC Bitesize?

A supervolcano is a volcano on a massive scale. It is different from a volcano because: it erupts at least 1,000 km 3 of material (a large volcano erupts around 1 km 3) it forms a depression, called a caldera (a volcano forms a cone shape) a supervolcano often has a ridge of higher land around it.

What is a supervolcano?

Supervolcanoes are capable of eruptions thousands of times larger than normal outpourings. It was thought that an external trigger, such as an earthquake, was needed to bring about a giant blast.

How do supervolcanoes erupt?

Supervolcanoes, however, begin life when magma rises from the mantle to create a boiling reservoir in the Earth’s crust. This chamber increases to an enormous size, building up colossal pressure until it finally erupts. The last supervolcano to erupt was Toba 74,000 years ago in Sumatra.

How many supervolcanoes are there on Earth?

There are about 20 known supervolcanoes on Earth – including Lake Toba in Indonesia, Lake Taupo in New Zealand, and the somewhat smaller Phlegraean Fields near Naples, Italy. Super-eruptions occur rarely – only once every 100,000 years on average. But when they do occur, they have a devastating impact on Earth’s climate and ecology.

How to simulate the intense pressure and heat of a supervolcano?

To simulate the intense pressure and heat in the caldera of a supervolcano, the researchers visited ESRF in Grenoble, where they used an experimental station called the high pressure beamline.

How do I calculate the number of years of service in Excel?

Calculate the Length of Service between a Previous Date and Present Date

1. =DATEDIF(B2, TODAY(), “y”)& ” Years”
2. =DATEDIF(B4,TODAY(),”y”)&” Years, “&DATEDIF(B4,TODAY(),”ym”)&” Months”
3. =DATEDIF(B6,TODAY(),”y”) & ” Years, ” & DATEDIF(B6,TODAY(),”ym”) & ” Months, ” & DATEDIF(B6,TODAY(),”md”) & ” Days”

How do you count years of service?

For the purpose of determining the number of years in a service period, divide the total number of calendar days in the service period by 365 and round the result to two decimal places. For example, a service period covering 39 biweekly pay period equals 546 days, and 546 days divided by 365 days equals 1.50 years.

How do you calculate years of service in sheets?

Another way to calculate the age in years in Google Sheets is by using the YEARFRAC function. The YEARFRAC function will give you the number of years (including fractional years), between two given dates.

How do you calculate 5 year anniversary in Excel?

If you want to get special anniversary of every staff, you could refer to following formulas. Anniversary: {=DATE(YEAR(TODAY()),MONTH(D6),DAY(D6))}; Anniversary numbers: {=YEAR(E6)-YEAR(D6)}; Special anniversary:{=IF(OR(F6=3,F6=1,F6=5),F6,” “)}.

How do you calculate tenure between months and years in Excel?

Step 1: In D2, enter the formula =DATEDIF(B2,NOW(),”Y”)&” years, “&DATEDIF(B2,NOW(),”YM”)&” months “. Then click Enter. Verify that 25 years and 3 months are displayed. Step 2: In D4, enter the formula =DATEDIF(B4,C4,”y”)&” years, “&DATEDIF(B4,C4,”ym”)&” months “.

How do I calculate year of anniversary in Excel?

If you want to get special anniversary of every staff, you could refer to following formulas. Anniversary: {=DATE(YEAR(TODAY()),MONTH(D6),DAY(D6))}; Anniversary numbers: {=YEAR(E6)-YEAR(D6)};

How long is service in Excel?

Enter the formula =DATEDIF(C2,D2,”y”)&” years “. Step 2: Only calculate the length of service with Month unit. Enter the formula =DATEDIF(C2,D2,”m”)&” months “. Step 3: Only calculate the length of service with Date unit.

How do I add 5 years to a date in Excel?

In your Excel worksheet, the formulas may look as follows:

1. To add years to a date in Excel: =DATE(YEAR(A2) + 5, MONTH(A2), DAY(A2)) The formula adds 5 years to the date in cell A2.
2. To subtract years from a date in Excel: =DATE(YEAR(A2) – 5, MONTH(A2), DAY(A2)) The formula subtracts 5 years from the date in cell A2.

How do I calculate months of service in Excel?

To find the number of months or days between two dates, type into a new cell: =DATEDIF(A1,B1,”M”) for months or =DATEDIF(A1,B1,”D”) for days.

How do I calculate months and years in Excel?

Calculate elapsed year, month and days Select a blank cell which will place the calculated result, enter this formula =DATEDIF(A2,B2,”Y”) & ” Years, ” & DATEDIF(A2,B2,”YM”) & ” Months, ” & DATEDIF(A2,B2,”MD”) & ” Days”, press Enter key to get the result.

How do I add 6 years to a date in excel?

How to subtract or add years to date in Excel

1. To add years to a date in Excel: =DATE(YEAR(A2) + 5, MONTH(A2), DAY(A2)) The formula adds 5 years to the date in cell A2.
2. To subtract years from a date in Excel: =DATE(YEAR(A2) – 5, MONTH(A2), DAY(A2)) The formula subtracts 5 years from the date in cell A2.

How do you calculate months of service in Excel?

– =DATEDIF (B2, TODAY (), “y”)& ” Years” – =DATEDIF (B4,TODAY (),”y”)&” Years, “&DATEDIF (B4,TODAY (),”ym”)&” Months” – =DATEDIF (B6,TODAY (),”y”) & ” Years, ” & DATEDIF (B6,TODAY (),”ym”) & ” Months, ” & DATEDIF (B6,TODAY (),”md”) & ” Days”

How to calculate length of service in Excel?

– Define important columns for calculating the length of service. To calculate the length of service, you need to know the employee’s employment date and if they still work for the – Learn to use the DATEDIF () function. – Calculate how many days are until the next service year.

How do you calculate the number of years in Excel?

– =INT (DAYS360 (DATE (2014,6,15),DATE (2018,6,27))/360) – =INT (YEARFRAC (B4,C4)) – =DATEDIF (B6,C6,”y”)

How to calculate the next anniversary date in Excel?

In the New Rule window,at the top,click ‘Use a formula to determine which cells to format’

Click in the Formula box,where you’ll add a rule that checks the anniversary date,to see if it is between the StartDate and EndDate.

Click the Format button,and select a colour to highlight the upcoming anniversaries – I selected bright green.

https://www.youtube.com/watch?v=H8KpLTLosSQ

What is the meaning of low density residential?

Low density, in real estate terms, describes the number of housing units per given unit of land in a particular area. Low density housing typically refers to residential areas occupied primarily by single-family homes or buildings with a small number of units.

What is a lower density use zone?

“Low density residential zones” are locations intended for housing that include a lot of open space. These zones are meant for a small number of residential homes, and exclude large industries, apartment complexes, and other large structures.

What does zones for R2 mean?

R2 (Residential, Low Density) District. The R2 zoning district identifies areas of the City characterized by low density development. The standards of the R2 zoning district are intended to maintain residential neighborhood character, and to ensure that new development is compatible with the existing character.

What is residential zonation?

Residential zoning includes single-family residences, suburban homesteads, and other designations like houses, apartments, co-ops, and condos. Residential zoning laws cover issues like whether a mobile home is allowed to be placed on a property and how many structures can be built on specific properties.

What does it mean to have a low density?

Definition: Density depends on how atoms or particles are arranged in matter in a specific volume. If the particles are loosely packed together with plenty of space between them, it will have a low density and will be able to float.

What is an example of low density housing?

In the field of housing, at the lower densities, these include such forms as single-family dwellings, semi-detached units (duplexes, etc.), row houses, and secondary in-law units.

What is an example of low density?

For example, wood floats on water because there is plenty of space between the atoms in the wood – that is – it has low density. An iron nail sinks in water because the atoms are tightly packed in the iron nail with very little space between them.

What does R2 low density residential mean?

R2 is a zone for land comprised mainly of low density housing where the planning objective is to protect the locality’s single dwelling character and landscape setting. The zone also allows for a variety of housing types, facilities and services to meet the needs of the community and residents.

What is R2 residential zoning Philippines?

ARE DUPLEXES AND SINGLE-ATTACHED DWELLINGS (RESIDENTIAL 2/ R-2 OR MEDIUM DENSITY RESIDENTIAL DWELLINGS) PERMITTED IN RESIDENTIAL 1/ R-1 ZONES INTENDED SOLELY FOR SINGLE-DETACHED DWELLINGS?

What is zoning in property?

The zoning ordinance is the formal categorization of land-use policies applicable to land within a municipality. It also sets the legal framework. The zoning ordinance establishes permitted land uses and distinguishes between different land use types.

What are the land-use zones?

Land-use zones are areas in urban areas that have particular functions, such as retail, residential and industry….The main zones are:

• CBD.
• Inner City.
• Suburbs.
• Rural-Urban Fringe.

What happens if the density is low?

An object that has a lower density than the liquid it’s in will float. You can really see relative densities at work when you look at a heavy object floating and a lighter one sinking.

What are the objectives of zone R2 low density residential?

Zone R2 Low Density Residential 1 Objectives of zone • To provide for the housing needs of the community within a low density residential environment. • To enable other land uses that provide facilities or services to meet the day to day needs of residents.

What is a low density zoning ordinance?

Low-Density Residential Zoning Ordinances Low-density residential zoning ordinances are implemented to limit the density of dwellings per unit of property, such as an acre. There is no uniform low-density zoning ordinance because each municipality generally enacts its own ordinance based upon its needs and preferences.

What zones are single-family dwellings permitted in?

Single-family dwellings are permitted in all zones except for UGC, M1, M3, and M4. RT1 (medium density residential, 1,350 square foot minimum lot size and intended for townhouses)

Are duplexes allowed in R2 zoning?

R2 & R2A (intended for two-family dwellings with a minimum 9,500 square foot lot size on sewers); Duplexes only permitted with a special permit approved by the Board of Zoning Appeals. Two-family dwellings are also permitted in R3MD, R3, R5, O1, C5, M1. Multi-family dwellings are also permitted in C5.