To solve this problem it is necessary to apply the concepts related to Current and Load.
The current in terms of the charge of an electron can be expressed as

Where,
q = Charge
t = time
At the same time the Charge is the amount of electrons multiplied by the amount of these, that is
q = ne
Replacing in the first equation we have to


Clearing n,

Here the time is one second then



Therefore the number of electrons per second are passing any cross sectional area of the wire are 
Air spaces are used in insulation because air is a poor conductor.
Answer:
what?
Explanation:
does that means also i learned Ratios and multiplication i keared them like 5 years ago?
Answer: it’s A and B
Explanation: everyone else on this post was giving you the wrong answer.