The red race car drives 21 miles in 15 minutes. find the miles per hour

Allie answered 72% of the questions on her math test correctly. if she answered 18 questions correctly, how many questions were on the test?

The amount of money, in dollars, in an account after t years is given by a = 1000(1.03)^t. the initial deposit into the account was $_^a0 and the interest rate was _a1% per year. only enter numbers in the boxes. do not include any commas or decimal points^t. the initial deposit into the account was $__^a0 and the interest rate is % per year.

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