Two charges q1 and q2 have a total charge of 16 C. When they are separated by 1.5 m, the force exerted by one charge on the other has a magnitude of 8 mN. Find q1 and q2 if (a) both are positive so that they repel each other, and q1 is the smaller of the two. (For the universal constant k use the value 8.99 109 N m2/C2.)