What’s the perimeter

What is the ratio for the surface areas of rectangle prisims shown below given that they are similar and that the ratio of their edge lengths is 7: 3

Look at attachment. has all info needed. need

Marco has $38.43 dollars in his checking account. his checking account is linked to his amazon music account so he can buy music. the songs he purchases cost $1.29. part 1: write an expression to describe the amount of money in his checking account in relationship to the number of songs he purchases. part 2: describe what the variable represents in this situation.