Answer:
C
Step-by-step explanation:
The sum to n terms of a geometric sequence is
= 
Here a₁ = 4 and r = - 3, thus
= 
=
= - (729 - 1) = - 728 → C
Answer:
213.52 cubic ft
Step-by-step explanation:
Diameter of pipe = 4ft
radius for circle is half of diameter
thus radius of pipe = 1/2 of 4ft = 2 ft
length of pipe = 17 feet
volume of cylinder is given by 
where r is the radius and l is the length of cylinder
.
thus volume of pipe is calculated below using above values

volume of pipe is 213.52 cubic ft.
I honestly don’t know what interest is can u please explain what it is??
The area of a triangle in determined by the formula:

where b is the base of the triangle and h is it's height
You just have to replace the b and h with their values in the formula (b=9.9ft and h=5.5ft)
The answer is 27.225 ft^2