Answer:

Step-by-step explanation:

Answer:
rent goes up 9 dollars at a time while number of days is 1 at a time
Step-by-step explanation:
the difference of 21 and 12 is 9 so you can see it changes every day by nine for the ratio i think is for every day 9 dollars is added to fee
The answer would be 24pi inches.
You can find this by using the formula for a circumference and plugging in the value of the radius.
C = 2pi*r
C = 2pi * 12
C = 24pi