Which of the following are geometric sequences (check all that apply)a.) 1, 1, 2, 3, 5, 8, 13b.) 10,5, 2.5, 1.25, 0.625, 0.3125c.) -9, -3, -1, -1/3, -1/9, -1/27d.) 5, 10, 15, 20, 25

B and C are geometric sequences.

Step-by-step explanation:

A geometric sequence is a sequence of numbers in which the ratio between consecutive terms is constant.

A is not a geometric sequence because the number 1 is repeated twice in the sequence.

B is a sequence because the sequence is being multiplied by 0.5 each time.

C is a geometric sequence because it is being multiplied by 1/3 each time.

D is not a geometric sequence because it is not being multiplied each time - it is increasing by +5 (arithmetic progression - not geometric).

Hope this helps!

answer: 21$

step-by-step explanation:

$42 / $14 = 3   (ratio 3: 1)

$7 x 3 = $21

answer:   c ?

step-by-step explanation: