Figure D shows (in cross section) a spherical metal shell with a hollow. A particle of charge Q is placed at the center of the shell (at the center of the hollow). The metal of the shell has a net charge of -8.0 E-6 C. The electric field at point P (which is 2.0 m from the center of the shell) has magnitude 6.743 E3 N/C outward. What is chargc Q of the particle in coulombs