If the geometric series has first term
and common ratio
, then its
-th partial sum is

Multiply both sides by
, then subtract
from
to eliminate all the middle terms and solve for
:



The
-th partial sum for the series of reciprocal terms (denoted by
) can be computed similarly:




We're given that
, and the sum of the first
terms of the series is

and the sum of their reciprocals is

By substitution,

Manipulating the
equation gives

so that substituting again yields

and it follows that

It would be ft3 because its a cone shape and you multiply the circumference by the height and you’ll get the volume
The answer is 10.
6^2/2(3)+4 is the formula
6^2=36
36/2(3)+4
2(3)=6
36/6+4
36/6
6+4
10
I did PEMDAS. P is for Parentheses. E is for exponents. M is for multiplication. D is for Division. A is for adding. S is for subtracting.