A student who weighs 550 N is wearing a backpack that weighs 80 N. The student is standing still on level ground. Give your answers to the following questions in newtons. Remember, enter only the number; don't try to enter the units.a) What is the magnitude of the net force on the student?
b) What is the magnitude of the contact force on the student by the backpack?
c) What is the magnitude of the contact force on the student by the ground?

a) The magnitude of the net force on the student = 0 N since the student is standing still on level ground and upward reaction force = downward force.

b) the magnitude of the contact force on the student by the backpack = 80 N since the student was backing the backpack

c) the magnitude of the contact force o the student by the ground = 550 N + 80 N = 630 N reactional force on the student