Question 18 of 18 Two point charges are enclosed by a spherical conducting shell that has an inner and outer radius of 13.0 cm and 15.2 cm, respectively. One point charge has a charge of q1 = 9.90 pC, while the second point charge has an unknown charge q2. The conducting shell is known to have a net electric charge of -4.10 pC, but measurements find that the charge on the outer surface 0 Macmillan Learning of the shell is 3.70 uC. Determine the charge q2 of the second point charge in units of microcoulombs. 42 HC