实验室保存药品时通常选用下图所示的试剂瓶．下列有关试剂保存的说法正确的是（ ）

烤烟B1K的油分为（）

A、有

B、少

C、稍有

D、多

Even though current technologies make the ultimate segmented network impractical, new technologies and products hold the promise of making the concept a reality. Most important of all these new technologies are (66) . The ultimate switched LAN, which is technically possible, now, exhibits the following characteristics:
1. High-speed yet cost-effective switching devices can be implemented on a wide scale, providing dedicated connections for individual users and supporting the aggregate (67) of all networked users.
2. The ability to deploy switching capabilities incrementally into the (68) base. Switching implementations support switching of individual users or groups so that existing users of shared media modules can continue to use the existing equipment until they can justify moving to dedicate switched LAN connections.
3. Support and enhancement of existing routed environments. Switching (69) routint, but rather can be introduced into the network without making any changes to the existing routing equipment or configuration. (70) play a critical role in the integration of switching into existing networks.

A．assigned

B．does not justify

C．replace

D．does not replace

物质的表面吸附是由于物质表面存在着（）。

A、表面重力

B、表面浮力

C、表面压力

D、表面张力

拼装高度为( )m以上的竖向模板，不得站在下层模板上拼装上层模板。安装过程中应设置足够的临时固定设施。

A．2
B．4
C．5
D．7

股票是指股份有限公司签发的证明股东所持股份的凭证，从中我们可以看出股票的基本要素有（）。

A.发行主体

B.股份

C.持有人

D.面值