Normal values of Qco2 = 200 mL min-1 (STPD); V = 510 mL (BTPS); VD = 150 mL (BTPS) and VR 12 min. During exercise, Qco2 increased to 1000 mL min (STPD) and VR increased to 20 min¹. A. What would VT be if PAC02 did not change? B. If R 0.8, calculate PA02 (assuming that PACO2 = 40 mm Hg)