Find the energy level of G-R centers in n-type (ND = 1016 cm-3) silicon, such that a trapped hole is as likely to be re-emitted into the valence band as it is to recombine with an electron. Assume that T = 300 K. Will G-R centers that are located above or below this level be more efficient as recombination centers? Assume that the capture cross-sections of holes and electrons are equal.