冬天含碳数较多的烃类较难气化的原因跟以下哪个液化石油气性质有关（）
A.热值
B.华白数
C.蒸汽压
D.密度
参考答案：C
句子改错。
( ) 1. ________ Here is the results of the students activity at No.5 Middle School.
A B C D
( ) 2. ________ The results for “playing tennis” are interested.
( ) 3. ________ Most primary school students watch TV everyday.
( ) 4. ________ Some boys play basketball once and twice a week.
( ) 5. _________ Sam is very active and does exercises every day.
球团矿的粒度在15mm-25mm的范围内最好。（）
