对录音棚早期反射声的要求是不能太少。( )
参考答案：对
When the baby saw her mother, she cried _____. [ ]
A. harder and harder
B. hard and hard
C. hard and harder
D. harder and hard
煤的发热量测定试验中要求实验室的温度在（）范围内。
A.15-20℃
B.20-25℃
C.20-30℃
D.15-30℃
