一根弹簧的原长为12 cm，它能挂的重量不能超过15 kg并且每挂重1kg就伸长

Water is (41) important of all the things we (42) and drink. Not many people understand this, (43) it’s quite true. The human body (人体) can go (44) food for a long time, but two (45) three days without water can usually (46) people die.
Many people don’ t understand how much water the human body needs to work well and many people do not drink (47) , even (48) hot weather.
Our body is (49) water, about 65% to 75%, ff we do not have enough water, we’ll (50) tired and many will get ill. So you see, how important water is to us all.

[A] or[B] and[C] in

手的骨性关节炎发病率随年龄而增长，最常见的情况是

A．绝经前妇女多于男性

B．在各种年龄都是男多于女

C．在各种年龄都是女多于男

D．男性多于绝经前妇女

E．年轻妇女

血液中乳酸增加是机体缺氧的重要指标之一，临床上危重病患者乳酸中毒是指（）

A.动脉血乳酸浓度＞1.5mmol／L

B.动脉血乳酸浓度＞2mmol／L

C.动脉血乳酸浓度＞3mmol／L

D.动脉血乳酸浓度＞4mmol／L

E.动脉血乳酸浓度＞5mmol／L

进入90年代，Internet事实上已成一个“网中网”，各个子网分别负责自己的建设和运行费用，而这些子网又通过 【16】 互联起来。

《空闲卧铺优惠发售办法》规定，列车空闲卧铺优惠幅度是多少？