It’s Due in 5mins! HELP

Look at the following graph of the given equation. determine whether the equation is a function. explain why or why not.

Me d is also an option but i couldn't get it in the picture

Which problem would you use the following proportion to solve for? 24/x=40/100 a. what is 40% of 24? b. what percent is 24 of 40? c. twenty-four is 40% of what number? d. forty percent of 24 is what number?