so no body wants to help me:

Two point charges are on the y axis. a 3.90-µc charge is located at y = 1.25 cm, and a -2.4-µc charge is located at y = −1.80 cm. (a) find the total electric potential at the origin. v (b) find the total electric potential at the point whose coordinates are (1.50 cm, 0). v

Most of the volume of an atom is occupied by the

Often called simply "velocity," this is the velocity of an object at a particular moment in time.