Answer:
the force between the two charges is 198.37 N
Step-by-step explanation:
Given;
charge of the first particle, Q₁ = -3 x 10⁻⁵ C
charge of the second particle, Q₂ = 9.0 x 10⁻⁵ C
distance between the two charges, r = 0.35 m
The force between the two charges is calculated from Coulomb's law;

where k is Coulomb's constant = 9 x 10⁹ Nm²/C²

Therefore, the force between the two charges is 198.37 N