**a)** Draw the free-body diagram for the box on the surface of the Earth. Hint: The direction of the normal force (i.e the force due to the ground) should make an angle with respect to the normal to the surface.

**b)** Write down the equations of motion for the box.

**c)** Find an expression for the magnitude of the normal force in terms of the quantities given in the problem.

**d)** Find an expression for the direction of the normal force with respect to the direction of the normal to the surface of the Earth.