Respuesta :

Answer:

The first choice is correct.

Step-by-step explanation:

First work out the common ratio r:-

a2 = a1r and a5 = a1 r^4

So r^3 = a1r^4 / a1r = 256/ 108

r = cube root (256/-108) =  4/3

So the explicit formula is 108(4/3)^(n-1)

Answer:

C. 81[-4/3]^n-1

Step-by-step explanation: