Help ;-; sorry if im asking again Replace the pencil with an iron nail (Doc.19 in pic)

1. does the lamp glow? (question)

2. does an electric current flow through the lamp? (question)

3. Does the iron nail conduct the electric current? (question)

The sun’s mass is 2.0×10^ 30 kg, its radius is 7.0×10 5 km, and it has a rotational period of approximately 28 days. if the sun should collapse into a white dwarf of radius 3.5×10 3 km, what would its period be if no mass were ejected and a sphere of uniform density can model the sun both before and after?