A point charge qı is held stationary at the origin. A second charge q2 is placed at point a, and the electric potential energy of the pair of charges is +5.4 x 10-8 J. When the second charge is moved to point b, the electric force on the charge does -1.9 x 10-8 J of work. Part A What is the electric potential energy of the pair of charges when the second charge is at point b? Express your answer in joules.

A point charge qı is held stationary at the origin. A second charge q2 is placed at point a, and the electric potential energy of the pair of charges is +5.4 x 10-8 J. When the second charge is moved to point b, the electric force on the charge does -1.9 x 10-8 J of work. Part A What is the electric potential energy of the pair of charges when the second charge is at point b? Express your answer in joules.