12.D
13.A
14.A
15.D
16.B
17.B
19.D
20A
Hello, Marymack!
We know that in a geometric sequence defined by
![\mathsf{a_1}](https://tex.z-dn.net/?f=%5Cmathsf%7Ba_1%7D)
and
![\mathsf{r}](https://tex.z-dn.net/?f=%5Cmathsf%7Br%7D)
, the sum can be calculated the following way:
Answer:
am I to find the p? are there any multiple question answers ?
Counting. Hope this helps. If not sure google it.