A stone of mass 0.6kg attached to a string of 0.5m is whirled in an horizontal circle of a constant speed. if the maximum tension (force) in the spring is 30N before it breaks. calculate (1) The maximum speed of the stone (2) The maximum number of revolution it can make.​

As newton's first law states a object in motion stays in motion

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

Potato’s are the right way to go promise not apples i’m 5