单项选择题
A.0.0045MPa B.0.0045-0.005MPa C.0.005-0.0055MPa D.0.006-0.0065MPa
A.提高 B.保持不变 C.降低 D.平衡
A.蒸汽初温 B.蒸汽初压 C.排气压力