In the diagram below, q1 = +4.50 x 10^-6 C, q2 = -3.25 x 10^-6 C, and q3 = +3.73 x 10^-6 C. Charges 1 and 2 are separated by 3.00 cm and charges 1 and 3 are separated by 1.50 cm. The constant in Coulomb's Law, k, is 8.99 x 10^9 N m^2/C^2. a) Determine the electric force acting on q1. b) Determine the electric field at q1.