I need helppp what’s the answer?!!?

f(x)=12-5(n-1)

Step-by-step explanation:

Let's look at the options.

The last 2 options both represent a geometric sequence, so that cannot be the answer.

Now, notice that the common difference between the terms in the sequence is -5. The first option suggests that that it is 5, while the second suggests that it is -5, so the second option is the correct one.

(a) the volume of the cone is 20/3 in3

hence, option a is correct.