The current in the electric lamp circuit is 0.3 A. How many electrons pass through the cross section of the spiral in 5 minutes.

We find the charge, knowing the current I = 0.3 A and the time t = 5 minutes = 5 * 60 s = 300 s.
q = 0.3 A * 300 s = 90 A * s = 90 C,
We take the electron charge from the tables: e = 1.6 * 10 ^ (- 19) Cl.
Dividing the entire charge by the charge of one electron, we get the number of electrons n:
n = q / e = 90 / 1.6 * 10 ^ (- 19) = 5.6 * 10 ^ 20 (total electrons).