A 664 μC Charge Is Placed at the Origin and a a Second

Multiple Choice

A 6.64 μC charge is placed at the origin and a second charge is placed on the x-axis at x = 0.2 m.If the resulting force on the second charge is 6.4 N in the positive x-direction,what is the force on the charge at the origin?
​

A) 6.4 N in the positive x-direction
B) 6.4 N in the negative x-direction
C) 0 N
D) not able to be determined until the second charge is known
E) ​6.4 N in the negative y-direction