Work is done when a force a. is exerted while pulling a wagon up a hill b. acts vertically on a cart that can only move horizontally c. is exerted by one team in a tug of war when there is no movement d. of gravitaional attarction acts on a person stabnding on the surface of the earth

An uncharged nonconductive hollow sphere of radius 18.0 cm surrounds a 12.0 µc charge located at the origin of a cartesian coordinate system. a drill with a radius of 1.00 mm is aligned along the z axis, and a hole is drilled in the sphere. calculate the electric flux through the hole.

What is hidden during a lunar eclipse? isn't the moon hidden?

Ineed the answer to question 1 , i’m desperate