每天人体要更新蛋白质（）
A.16%
B.13%
C.10%
D.5%
E.3%
参考答案：E
— ____ locks do you have?
— I have four locks.[ ]
A. Who
B. How many
C. Where
加工精度分为（）类.
A.6
B.5
C.4
D.3
