A.X2,1=0.5,X2,2=0.5B.X2,1=0.25,X2,2=0.5C.X2,1=0.25,X2,2=0.75D.X2,1=0.5,X2,2=0.25
A.層流;140°;高B.層流;82°;低C.湍流;140°;低D.湍流;82°;低
A.對流換熱B.氣體的導熱及對流C.氣體的導熱D.熱輻射