12. which one of the following is a geometric sequence? a. −7, 10, 23, 36, . . b. 8, 4, 2, 1, 1/2, 1/4, . . c. 2, −3, 9/2, −18/4 d. 0, 1, 2, 3, . .

Step-by-step explanation:

A geometric sequence or geometric progression is a sequence where each term after the first one can be found by multiplying a certain factor.

So, basically, to find the geometric sequence, we just need to divide the second term by the first term and observe if it results a constant factor.

By doing that, we observe that the second equence is a geometric sequence with a reasonf of 1/2, let's demonstrate it

As you can observe, we perfectly built the sequence is its ratio or factor.

Therefore, choice B is a geometric sequence.

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step-by-step explanation:

1+2+3+4+5+6+7+8+9+10 = 55

2*10 = 20

55-20 = 35

you probably already have the answer but anyways it's b. 15.0

step-by-step explanation: