Physics · WORK, ENERGY AND POWER

A woman pushes a crate on a rough floor. For the first \( 12\text{ m} \), she applies a constant force of \( 120\text{ N} \). Over the next \( 8\text{ m} \), her applied force decreases linearly to \( 40\text{ N} \). Throughout the motion, an opposing frictional force of \( 60\text{ N} \) acts on the crate. The net work done on the crate during the entire \( 20\text{ m} \) displacement is:

1. A
   \( 2080\text{ J} \)
2. B
   \( 880\text{ J} \)
3. C
   \( 1200\text{ J} \)
4. D
   \( 640\text{ J} \)