1.95 mol of a perfect gas with Cv = 3/2R undergoes the transformation described in the following list from an initial state described by T = 290.0 K and P = 1.00 bar. Calculate q, w, ?U, ?H, and ?S for each process. a) The gas is heated to 520.0 K at a constant external pressure of 1.00 bar b) The gas is heated to 520.0 K at a constant volume corresponding to the initial volume c) The gas undergoes a reversible isothermal expansion at 290.0 K until the pressure is half of its initial value