For the cases below, a closed system undergoes a process in which work is done on the system and the heat transfer Q occurs only at a location on the boundary where the temperature is Tb. For each case, determine whether the entropy change of the system is positive, negative, zero, or indeterminat. a. internally reversible process, Q > 0.b. internally reversible process, Q = 0.c. internally reversible process, Q < 0.d. internal irreversibilities present, Q > 0.e. internal irreversibilities present, Q = 0.f. internal irreversibilities present, Q < 0.