Solve the Problem $40,20,10,5 , \frac { 5 } { 2 } ; a _ { n } = \frac { 80 } { 2 ^ { n - 1 } }$

Multiple Choice

Solve the problem.
-While bungee jumping, Gregory falls from a height of 80 feet. He continues to bounce one-half the height from which he last fell. Write out the first five terms of this geometric sequence and find the general term.

A) $40,20,10,5 , \frac { 5 } { 2 } ; a _ { n } = \frac { 80 } { 2 ^ { n - 1 } }$
B) $80,40,20,10,5 ; a _ { n } = \frac { 80 } { 2 ^ { n - 1 } }$
C) $80,78,76,74,72 ; a _ { n } = 80 - 2 ( n - 1 )$
D) $80,40,20,10,5 ; a _ { n } = \frac { 80 } { 2 ^ { n } }$