In the figure four particles are fixed along an x axis, separated by distances d = 3.50 cm. The charges are q1 = +4e, q2 = −e, q3 = +e, and q4 = +12e, with e = 1.60×10−19 C. What is the value of the net electrostatic force on (a) particle 1 and (b) particle 2 due to the other particles? (a) Number Units (b) Number Units