I am moving and had to pack all of my things. I pushed the boxes with a force of 15N to the left, and there was a frictional force of 7N. What is the net force? *

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?