PLZ HELP Determine if the sequence is arithmetic or geometric, and find the common difference or ratio.

x 1 2 3 4
f(x) 81 72 63 54
Arithmetic, common difference = 9
Arithmetic, common difference = −9
Geometric, common ratio = 9
Geometric, common ratio = −9

the answer is  

a.

4,624π mm2

step-by-step explanation:

yes, gavin is right.

step-by-step explanation:

gavin is correct. 

this problem is about converting 9% per year to how many percent per quarter. the rate is still the same. it only differed in the time period. so, through dimensional analysis,

9% per year  × (1 year / 4 quarters) = 2.25% per quarter

if he was asked to convert 9% per year to how many percent per quarter  compounded quarterly, then you will not simply divide by four. this is because compounding is not linear.

hope this , have a good day. c;