Spud's mom is going to make him a round birthday cake, and has asked for your help. Spud is a bit weird, and has already announced that when he slices the cake, your slice will have a perimeter of 16 inches, because you're his favorite friend, and
that's his favorite number. Since you're helping his mom with the baking, what diameter cake will you recommend she makes
so that you end up with the most possible cake at weird Spud's party? (Hint: you can ignore the thickness of the cake, since
this will be the same, regardless of its diameter.)