Mutt Daycare was reviewing the water bill for their doggy day spa and determined that his highest bill, $4,300, occurred in June when they washed 1,300 dogs and his lowest bill, $3,900, occurred in February when they washed 900 dogs. (Show all work)

a. What was the variable rate for Mutt Daycares water bill?

b. What was the fixed rate for Mutt Daycares water bill?

c. What would Mutt Daycares water bill be if they washed 1,200 dogs?