Three Point Charges Are Positioned on the X Axis $\mu$ C at X = 0,+20

Multiple Choice

Three point charges are positioned on the x axis.If the charges and corresponding positions are +32 $\mu$ C at x = 0,+20 $\mu$ C at x = 40 cm,and -60 $\mu$ C at x = 60 cm,what is the magnitude of the electrostatic force on the +32- $\mu$ C charge?

A) 84 N
B) 12 N
C) 36 N
D) 50 N
E) 48 N