If the torque required to loosen a nut that
is holding a flat tire in place on a car has a
magnitude of 34 n · m, what minimum force
must be exerted by the mechanic at the end
of a 30 cm-long wrench to loosen the nut?
answer in units of n

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

I’m not sure about this question