Joe and kim washed 27 cars in 6 hours. the next day, they had more and washed twice as many cars in the same amount of time. what was their average car-washing rate on the second day?
a. 4.5 cars per hour
b. 5 cars per hour
c. 6.2 cars per hour
d. 9 cars per hour

Becca wants to mix fruit juice and soda to make a punch. she can buy fruit juice for $3 a gallon and soda for $4 a gallon. if she wants to make 28 gallons of punch at a cost of $3.25 a gallon, how many gallons of fruit juice and how many gallons of soda should she buy?