Yes, exponential or log I think! It is a function — use vertical line test
Tripling the height will triple the volume.
Formua is r^2 *

* height.
If you triple the radius, you must still square it, so it will be 9 times bigger.
If you triple the height, then it will be 3 times bigger.
Answer: C - the fourth month
Step-by-step explanation: If it doubles every month, then at 6 months there should be 32 times the original affected area. 1/8 of 32 is 4.
Hmmm... a geometric sequence MUST have a fixed common ratio. If it is changing, then the sequence you are looking at might not be a geometric sequence at all. We'd need to see an example to be sure.