PLEASE HELP ME! WILL MARK BRAINLIEST!! :D

Given the explicit formula for a geometric sequence, find the first 5 terms and the 8th term. **(I already have the answers for the 8th term, I just need help finding the first 5 terms of each equation)**

aN = 3^8-1 = 2,187; 8th term
aN = 2 * (1/4)^8-1 = 0.000122; 8th term
aN = -2.5 * 4^8-1 = -40,960; 8th term
aN = -4 * 3^8-1 = -8,748; 8th term