The rule for the number of fish in a home aquarium is 1 gallon of water for each inch of fish length. marta's aquarium holds 24 gallons of water and hanks aquarium hold 42 gallons of water. the aquarium holds two types of fish, fish a and fish b. if marta bought 3 of fish a and 2 of fish b, and hank bought 3 of fish a and 4 of fish b, how long is fish a and how long is fish b?