关于实验室个人防护，下列叙述错误的是：（）A．在实验室工作的所有时间内都必须穿工作服

1916年1月《农商公报》记载：“济南棉花之行情，日日变动。其原因，一方为需要供给之关系，他方为占输出棉花之大部分者，首日本，因之大阪行情时时变动，故济南市场亦因之受影响焉。济南重要之花行，有每日致电大阪询问行情者。”这反映出 [ ]

A．中国已沦为资本主义世界市场的一部分

B．中国农产品的市场价格由日本决定

C．中国近代农产品生产的商品化、专门化趋势日益明显

D．中国 * * 和海关的半殖民地化的现实状况

说明接近传感器的应用、常见种类及工作原理。

测试机的相关系数r大小为r1=-0.9，r2=0，r3=0.9，则以上三个数的相关强弱为：（）。

A.r1>r2>r3

B.r3>r2>r1

C.r1=r3>r2

D.r1=r3

Many geologists theorize that the trail of volcanic craters and cinder cones along the Snake River plain of southern Idaho was produced as the North American continent slid westward over a stationary "plume," a vertical channel through which molten rock rose intermittently from the Earth’s core to burst through its crust.
Which of the following, if true, tends to support the geologists’ theory of how the trail was produced

A．The largest craters and cinder cones are on the eastern margin of the trail.

B．The most violent volcanic activity apparently occurred at the western margin of the trail.

C．The craters and cinder cones are evenly spaced throughout the extent of the trail.

D．The newest craters and cinder cones are on the eastern margin of the trail.

E．(E) The craters grid cinder cones on the western margin of the trail generally took longer to form than did those on the eastern margin.

气体流速越大，吸附剂吸的附效果（）。

A.不变

B.越好

C.越差

D.无法确定