What two factors use to calculate work

Aray of light traveling parallel to the principal axis of a concave mirror will be reflected through the mirror's

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

If an atom contains 11 protons in its nucleus, predict the element with the atomic number and electronic configuration. will the number of electrons remain the same during the chemical reaction in such an atom? explain.