Question

what type of force is the contact force between the box and the track at time 4?
energy transfers and contact forces in the launcher, cart, box, and track system

air resistance
helping force
sound force
friction force

Explanation:

When two objects are in contact and moving (or tending to move) relative to each other, the contact force that opposes the relative motion is friction. In this case, the box is in contact with the track. Air resistance acts due to the motion through air (not relevant here as it's a contact force between box and track). "Helping force" is not a standard physics term. "Sound force" is not a valid force in the context of mechanics. Friction force is the contact force that acts between two surfaces in contact (here, box - track) and opposes the relative motion (or tendency of motion).

Answer:

Friction force