Một vật được thả rơi không với vận tốc đầu, khi vừa chạm đất có vận tốc 10 căn 2, coi như vật rơi tự do, lấy g= 10m/s^2a) xác định độ cao nơi thả vậtb) tính thời gian rơi của vật

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///(d) atoms contain small,negatively charged particles;

Cannot be determined because i dont  know this but i need the points