【简答题】8位子网掩码写作______,16位子网掩码写作______,24位子网掩码写作______。(答案用点分十进制写)
【简答题】从商品库的商品表1中查询出数量大于10的商品记录数。
【判断题】现行宪法第二十四条修正案把《宪法》第33条增加一款,作为第三款:“国家尊重和保障人权。”()
【单选题】When I went home, they had already ______ for the North.
【单选题】Which of the following statements about the poly(A) tails that are found on most eukaryotic mRNAs is correct?
A.
They are added as preformed polyriboadenylate segments to the 3 ′ ends of mRNA precursors by an RNA ligase activity.
B.
They are encoded by stretches of polydeoxythymidylate in the template strand of the gene.
C.
They are added by RNA polymerase II in a template-independent reaction using ATP .
D.
They are added by poly(A) polymerase using ATP and the conservative AAUAAA sequence is required .
【简答题】LED 显示器根据二极管的连接方式可以分为 和 两大类。