An object has a force on it given by F = (4.75 N)i + (7.00 N)j + (3.50 N)k.
(a) Find the magnitude of the force.
(b) Find the projection of the force in the x-y plane. That is, find the vector in the x-y plane whose head is reached from the head of the force vector by moving in a direction perpendicular to the x-y plane.