Please help with the following questions

l. (a) State Coulomb's Law. [1] (b) Two electrons are 4.2xl0'3m apart. What force do they repel each other with? [3] [Use Qe = 1.6 x 10"9C and k = 9.0 x109 Nm'C'Z] (c) A charge of +8 LjC and a charge of 4DC are 60cm apart. Where should a third charge be placed so that no net electrostatic force acts on it? [6] 2. (a) Fig 2.1 shows a circuit containing three capacitors and a battery. 4uF I ll ZuF : T ZuF PM 20V Figure 2.] Find: (i) the equivalent capacitance of the circuit. (ii) the charge stored by each capacitor. (ii) the p.d. across each capacitor. (iii) the total energy stored by the three capacitors. [10]