Answer:
3 Pounds for 15.10
Step-by-step explanation:
find a common multiplier (12)
4 pounds ($21.50) [×3] 12 pounds ($64.50)
3 pounds ($15.50) [×4] 12 pounds ($ 62)
you save $2.50
The general form would be:

where 'a' is responsible for the magnitude of the function, 'b' is responsible for horizontal shift.and 'c' is responsible for vertical shift of the function.
Your answer would be:

Looks like choice A
Circumference: radius
Circumference: twice the radius

and surely you know what that is
The answer is 26 and 16
26-16=10 so thats correct
and
26+16=42