Answer:
4x+12
Step-by-step explanation:

we know that given terms were i geometric progression.
which means common ratio is same between two consecutive terms .
here we have 8,40,200,1000.
we know that common ratio =second term/first term =40/8=5.
so each and every terms is multiplied by 5 to get next term for this series the term after 1000 is 5000 =1000*5.
in part b we have another series which is having common ratio of -2.
so we need to multiply with -2 to find next term.
80*(-2)=-160.
for part c the common ratio is -2 .
so we need to multiply with -2 *previous term =-2*16 =-32.
Volume = Length x Length x Length
Volume :
(x + 2) (x + 2) (x + 2)
= (x² + 4x + 4)(x + 2)
= x³ + 2x² + 4x² + 8x + 4x + 8
= x³ + 6x² + 12x + 8
Answer: x³ + 6x² + 12x + 8
I believe the answer is 3x^3
since 3 is the greatest common factor for the whole number and both have at least x to the third