What is the current through resistor #1? (must include unit - A)

3A

Explanation:

First, we must calculate voltage by summing the reciprocal of the resistances in the circuit

1/40 +1/40 = 2/40 = 1/20 = 1/R, so R = 20Ω

Using Ohm's Law, I = V/R, so the current I is I = 120/20 = 6A

Using Kerchoff's Circuit Law, we know that current will split evenly at a junction, so each resistor will get one half, or 3A.