远缘杂交使群体()。
A.纯合体增加
B.杂合体增加
C.走向分化
D.平均值提高
参考答案:B
A data warehouse is a subject-oriented data set used for reporting and analusis. Data warehouses can be subdivided into ( ). Which store subsets of data from a warehouse.
A. OLTPs
B. transactions
C. data sarts
D. OLAPs
氨是一种无色无味的气体,极易溶于水,1体积水可溶解700体积氨气。