An iron rod of length 50m and at a temperature of 60°C is heated to 70°C
Calculate its new length [linear
expansivity of iron = 1.2 x 10K

Ireally just need to get finished with precal! i’m really sorry i have to do this! hope this !

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