DNA在30nm纤丝中压缩多少倍？（）
A．6倍
B．10倍
C．40倍
D．240倍
E．1000倍
F．10000倍
参考答案：C
Every minute is made full _______ of _______ our lessons well.
A．to use; study
B．use; studying
C．use; to study
D．used; studying
肠内营养的注意事项有哪些？
