A.流體被加熱時(shí)取0.3,被冷卻時(shí)取0.4 B.流體被加熱時(shí)取0.4,被冷卻時(shí)取0.3 C.液體被加熱時(shí)取0.4,氣體被加熱時(shí)取0.3 D.液體加熱時(shí)取0.3,氣體被加熱時(shí)取0.4
A.1 B.2 C.3 D.4
A.增大 B.減小 C.不變 D.不好確定