The kinetic energy of the lead car

Q1. A crate of fragile dishes is in the back of a pickup truck. The truck accelerates north from a stop sign, and the crate moves without slipping. Does the friction force on the crate point north or south? Or is the friction force zero? Explain in complete sentences.
A 10,000 kg railroad car is rolling at 2 m/s when a 400 kg load of gravel is suddenly dumped in. What is the railroad car's speed just after the gravel is dumped in?
Q2. A high-speed drill reaches 2000 rpm in 0.50 s. What is the drill's angular acceleration? Through how many revolutions does it turn during this first 0.50s?
A 0.2 kg plastic cart and a 20 kg lead cart both roll without friction on a horizontal surface. Equal forces are used to push both carts forward a distance of 1.0m, starting from rest. Is the kinetic energy of the plastic cart greater than, less than, or equal to the kinetic energy of the lead car?

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