A point charge q1 = 4.15 nC is located on the x-axis at x = 2.10 m, and a second point charge q2 = -6.10 nC is on the y-axis at y = 1.00 m. What is the electric potential at the origin?
a) -6.12 kV
b) -8.25 kV
c) -10.15 kV
d) -12.30 kV