钢筋混凝土用钢筋，非合金构成，直径20mm，热轧后未经其他加工，带有轧制过程中产生的变形，直条状报验
参考答案：16（7214.2000）
Jeff goes to work _____ and his wife goes to work _____.[ ]
A. by car; on her bike
B. by a car; on her bike
C. by cars; by bike
D. by his car; by bike
酶耦联反应与一般酶反应的重要区别是（）
A.有明显的延滞期
B.快速
C.准确
D.误差小
E.误差大
