Question

1.A rectangle is placed around a semicircle as shown below. The width of the rectangle is 9mm. Find the area of the shaded region.

Use the value3.14 for pi , and do not round your answer. Be sure to include the correct unit in your answer.
2.A rectangular paperboard measuring 29 in long and 22in wide has a semicircle cut out of it, as shown below.
Find the area of the paperboard that remains. Use the value 3.14 for pi, and do not round your answer. Be sure to include the correct unit in your answer.
3.The radius of a cylindrical construction pipe is 2. If the pipe is 19 long, what is its volume?
Use the value 3.14for pi , and round your answer to the nearest whole number.
Be sure to include the correct unit in your answer.
PLS HALP

Answer 1

Since figure is not given, assume drawing a rectangle and label it from left top to right top as A and B. Similarly label it as C and D from bottom left to right. Draw a semicircle starting from C to D inside the rectangle.

You are asked to find area of shaded region which I assume is semicircular part.

Area of a circle is determined by Pi × r ^2

r is the radius of circle which is half of diameter. The diameter of circle is same as width of rectangle. So radius = 7/2 = 3.5 mm And area of shaded region is

1/2(Pi×r^2) = 1/2(3.14×3.5^2) = 19.2325 sq mm

Explanation: