1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
lana [24]
2 years ago
7

A building engineer analyzes a concrete column with a circular cross section. The circumference of the column is 18π meters. Wha

t is the area of the cross section?
Mathematics
1 answer:
Whitepunk [10]2 years ago
7 0
Answer: 81pi square meters

--------------------------------------------------------

Work Shown

C = 18pi is the given circumference
d = diameter which is unknown

C = pi*d
18pi = pi*d
18 = d
d = 18

The diameter is 18 meters.
Half of this is the radius r = d/2 = 18/2 = 9
The radius is 9 meters

Use the value of r to find the area of the circle
A = pi*r^2
A = pi*9^2
A = pi*81
A = 81pi

The area of the circular cross section is 81pi square meters

You might be interested in
Answer it and show your work. Which letter choice is it.
ivanzaharov [21]

Answer:

b = 55 degrees

Step-by-step explanation:

The angles 30, a, b and 45 must sum up to 180 degrees

Subtracting (30 + 45) from both sides leaves us with a + b = 105 degrees.

But b = a + 5.  Substituting a + 5 in the equation above yields

a + a + 5 = 105 degrees, so that

2a = 100 degrees, and a = 50 degrees.  Then b = a + 5, or b = 55 degrees.

7 0
3 years ago
Question : WHICH OF THE LINES IS PARALLEL ? HOW DO YOU KNOW ? ​
aleksandr82 [10.1K]

Answer:

B and R

I think that is the name of the lines. If not the the first two lines!!!!

8 0
2 years ago
Three ballet dancers are positioned on stage. Greta is straight behind Bryan and directly left of Alice. If Bryan and Greta are
Neko [114]

Answer:

12

Step-by-step explanation:

4 0
2 years ago
Please help me!! ......
fenix001 [56]

Answer:

b)480 cm^2

Step-by-step explanation:

perimeter=(16+12+20) cm

=48 cm

lateral surface area= perimeter × height

=48×10 =480 cm^2

4 0
3 years ago
Put the following list of numbers in ascending order.<br> ​1.2 0, -0.4, -2.6, 0
Elza [17]

Answer:

-2.6, -0.4, 0, 1.2

Step-by-step explanation:

tell me if i'm wrong :)

8 0
3 years ago
Read 2 more answers
Other questions:
  • Please Help
    11·2 answers
  • F(x) = –2x2 + 17<br> Find f(10)
    10·2 answers
  • Round to the nearest tenth of a percent<br><br> $89.54 ÷ $133.78
    14·1 answer
  • Question Help Find the original price of a pair of shoes if the sale price is $11 after a 75% discount.
    13·1 answer
  • Which best proves why the expressions 4 (x + 3) + 2 x and 6 (x + 2) must be equivalent expressions?
    8·2 answers
  • Part B
    13·1 answer
  • HELP ILL MARK BRAINLIEST <br> Please just do questions 4. And 5.
    13·2 answers
  • [ tan2 θ ] – [( sec θ – 1 )( sec θ + 1 )
    15·1 answer
  • A piece of fabric is in the shape of a triangle as shown below. Find the missing angle measure.​
    10·1 answer
  • On a number line, between which two consecutive whole numbers would √221 be located? Use pencil and paper. Explain why it might
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!