A friend has given you a special gift, a box of mass 10.0 kg with a mystery surprise inside. The box is resting on the smooth (frictionless) horizontal surface of a table.
a. Determine the weight of the box and the normal force exerted on it by the table.
b. Now your friend pushes down on the box with a force of 40.0 N. Again, determine the normal force exerted on the box by the table
c. If your friend pulls upward on the box with a force of 40.0 N, what now is the normal force exerted on the box by the table?
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