What property is this (8x5) x 10=8x(5x10)

What is the name used to describe a graph where for some value of x, there exists 2 or more different values of y?

The cost of turkey is directly proportional to its weight. if a 12-pount turkey costs $27, how much does a 13-pound turkey cost? a. $33.75 b. $36.00 c. $31.00 d. $32.50

Problem 3 a bank charges a service fee of $7.50 per month for a checking account. a bank account has $85.00. if no money is deposited or withdrawn except the service charge, how many months until the account balance is negative