Me with this! will give brainliest for quickest answer! 1. which of the following is a geometric sequence? a. 1, 8, 27, 64, 125, b. 3, -3/2, 3/4, -3/8, 3/16, c. 4, 7, 10, 13, 16, d. 25, 20, 14, 7, -1, 2. what is the common ratio r in the following geometric sequence? 10, 10/3, 10/9, 10/27, 10/81, a. -1/3 b .3 c. 10 d. 1/3

1. A geometric sequence has a common ratio. You can find the ratio by dividing every number by its previous one. If it is consistent, then the series is geometric.
a: 8/1=8, 27/8=3.375
b: (-3/2)/3=-1/2, (3/4)/(-3/2)=-1/2
c. 7/4=1.75, 10/7=1.429
d. 20/25=0.8, 14/20=0.7

Choice b is the only one that has a common ratio, so it is a geometric series.

2. Every term is multiplied by 1/3, so the common ratio is 1/3. d is the answer.