Name the parts of an atom and how each is charged, either positive, negative or neutral or uncharged

With i really need the correct answer!

Light that is polarized along the vertical direction is incident on a sheet of polarizing material. only 96% of the intensity of the light passes through the sheet and strikes a second sheet of polarizing material. no light passes through the second sheet. what angle does the transmission axis of the second sheet make with the vertical?

What is part of a line has one endpoint and continues in one direction?