简述lac的调节机制？

我国宪法第4条规定：“各少数民族聚居的地方实行( )，设立自治机关，行使自治权。”

A．民族自治

B．区域自治

C．完全自治

D．依法自治

金沙区法院在开庭审判徐某交通肇事案的过程中，徐某的辩护人请求通知新的证人到庭并请求重新勘验。依照法律规定，法庭正确的做法是什么( )

A．应当决定延期审理

B．应当决定中止审理

C．可以决定延期审

D．可以决定中止审理

Artificial flowers are used for scientific as well as for decorative purposes. They are made from a variety of materials, such as wax and glass, so skillfully that they can scarcely be distinguished from natural flowers. In making such models, painstaking and artistry are called for, as well as thorough knowledge of plant structure. The collection of glass flowers in the Botanical Museum of Harvard University is the most famous in North America and is widely known throughout the scientific world. In all, there are several thousand models in colored glass, the work of two artist-naturalists, Leopold Blaschka and his son Rudolph.

The intention was to have the collection represent at least one member of each flower family native to the United States. Although it was never completed. It contains more than seven hundred species representing 164 families of flowering plants, a group of fruits showing the effect of fungus diseases, and thousands of flower parts and magnified details. Every detail of these is accurately reproduced in color and structure. The models are kept in locked cases as they are too valuable and fragile for classroom use.

Which of the following is NOT included in the display at the Botanical Museum of Harvard University（）

A. Models of 164 families of flowering plants.

B. Magnified details of flower parts.

C. Several species of native birds.

D. A group of diseased fruits.

洋地黄中毒引起室上性阵发性心动过速的首选治疗是（）

A.静滴氯化钾

B.奎尼丁口服

C.阿替洛尔

D.利多卡因

E.电击复律

释水的BOD₅不应超过（）mg/L.

A、1

B、0.2

C、2

D、0.5