某药的反应速度为一级反应速度,其中k=0.02018,那此药的有效期为多少小时( )
A.50hB.20hC.5hD.2hE.0.5h
参考答案:C
Shopkeeper: 小题1:
Tim: Hello, I’m looking for a pair of football boots for my father.
Shopkeeper: Which color do you like?
Tim: I like the red ones. 小题2:
Shopkeeper: They’re 150 yuan
Tim: Oh! 小题3: How about the blue ones?
Shopkeeper: 140 yuan.
Tim: Also too expensive, 小题4:
Shopkeeper: Yes, The while boots cost only 100yuan .And they’re good.
Tim: Let me see 小题5:
下列不属于牛膝功效的是()
A.活血通经
B.强健筋骨
C.引火归原
D.利尿通淋
E.补益肝肾