成人男性体液总量占体重的（）
A.45%
B.50%
C.55%
D.60%
E.65%
参考答案：D
—How many on the cake?
—Three. Tom is three years old.[ ]
A. candles
B. pencils
C. apples
煤粉燃烧器应满足哪些要求？
