Each time the boy breathes, he exhales 0.5012 L of gas. How many moles of gas does he exhale?

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.

Sorry i dont understand the question can you rephase it?

Ametal with a large number of free flowing electrons most likely has good conductivity