What is the force experienced by a positive test charge of 6.4 × 10^(-6) coulombs if the electric field strength is 2.8 × 10^5 newtons/coulomb?
a) 6.4 × 10^(-6) newtons
b) 2.8 × 10^5 newtons
c) 1.7 × 10^(-2) newtons
d) 2.8 × 10^(-5) newtons