Auniform electric field = e0 is set-up in a region of space. a frame is placed in that region in such a way that its plane is perpendicular to the y-axis. which of the following changes would decrease the magnitude of the electric flux through the frame?

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

Since the pully is a simple machine so the mechanical advantage is a 1

The answer is -6hope this