When you ride a bicycle at constant speed, nearly all the energy you expend goes into the work you do against the drag force of the air. Model a cyclist as having cross-section area 0.41 m2 and, because the human body is not aerodynamically shaped, a drag coefficient of 0.90.

Amplify and switch electrical power and electronic signals

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

Answer(b) both involve the use of levers;

Electrical charge is measured in coulomb.(c). the amount of an electrical charge that moves in a circuit depends on the current flow and how long it flows for. a current of 10 a flows for 30 s,then 10 x=300 coulombs of electrical charge moves