A metal frame is pulled out of magnetic field at a constant velocity LaTeX: \small \vec{v}v → by a force LaTeX: \vec{F}_{pull}F → p u l l. The metal frame has resistance R and the changing magnetic flux induces a current LaTeX: ii in the frame. The magnetic field acting on the induced current generates a force LaTeX: \vec{F}_BF → B. Neglect all other forces.

Some type of thing that was invisible

A., d., and f i think

The car would move to the right with 150 n of force. the 150 n of force from friction and air resistance slows the car from moving to the right with 300 n of force.

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current