A student measures the time it takes for two reactions to be completed reaction eight is completed and 57 seconds and reaction be is completed and 48 seconds what can about the rights of these reactions

The answer to this problem is 1200

Alkaline earth metals are found in group 2 of the periodic table.

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