Question

1) Medical researchers have found a way to grow new skin from stem cells created from a patient's own skin. If a patient has been burned and needs a skin transplant for 50 cm2 of skin, using your general knowledge of the average size of a mammalian cell, estimate the number of cells that would need to be grown to cover the transplant area. Assuming that a stem cell (and all its descendants) can be made to divide once a day, how long would it take to grow enough for the patient?

2)Two students decide to go to Jerry's for a pizza. When they get there they find Jerry's is having a special.

SPECIAL TODAY
one 20' pizza	$15
REGULAR PRICE
one 10' pizza	$5
one 20' pizza	$18

Raphael goes: "Great! Let's get a large one." Donatello goes: "Don't be dumb. Let's get three of the small ones for the same price. That'll give us more pizza and be cheaper."

Raphael goes: "Why would it be a special if it's more than we could get for the regular price? Let's get the large."
Who's right? Which would you buy? What would the difference be if you were buying them at Ledo's (square pizzas)? Be sure to explain your answers.

Answer 1