汽包水位计损坏如何处理？

风险评价方法不是决定风险评价结果的唯一因素

It is hard to avoid mistakes.             you correct them, it will be all right.

A．As long as

B．Although

C．In case

D．Even though

在《验证机械能守恒定律》的实验中，下列说法中正确的               。

A．要用天平称量重锤质量

B．选用重物时，同样大小、形状的重物应选重一点的比较好

C．要选用第1、2两点距离接近2mm的纸带

D．实验时，当松开纸带让重锤下落的同时，立即接通电源E． 实验结果总是动能增加量略小于重力势能的减小量。

Passage One

Why was the world market important for the United States agriculture a. It provided evidence that Jefferson’s ideal could be achieved. b. It made farmers less dependent on local bankers. c. It affected the prices that farmers could receive for their crops. d. It decreased the power of the railroads to control farm prices.

包绕胰头的结构是：

A．门静脉

B．肝动脉

C．胆总管

D．十二指肠降部和横部

E．下腔静脉