How is the correct way to solve this?

If anyone has done the algebra 2 chaos theory portfolio would you be wiling to me? i kind of know what i'm doing i just don't know if i'm doing it right.

Organic apples are on special for $1.50 per pound. does total cost vary inversely or directly with the number of pounds purchased? find the cost of 3.4 pounds of apples. a. inversely: $5.10 b. directly; $5.10 c. inversely: $2.27 d. directly; $2.27

Consider circle c with angle acb measuring 3/4 radians.if minor arc ab measures 9 inches, what is the length of the radius of circle c? if necessary, round your answer to the nearest inch.