7. Determine the velocity of the electron in a positronium atom which is shown in the figure (figure is attached). Assume the radius of the positronium atom is 2 x 5.3 x 10 cm

a) What is the total angular momentum about the center of the positronium atom in Problem 7?

b) What is the force on the electron due to the positron? (Give both magnitude and direction.)

c) What is the electric potential energy of the positronium atom?