某CPU主频为8MHz,设每个CPU周期平均包括4个节拍周期(主频周期),且该机平均指令执行速度为1MIPS。 ① 求该机平均指令周期。 ② 求每个指令周期包含的平均CPU周期。③ 若改用主频周期为0.01μs的CPU芯片,试计算平均指令执行速度可提升到多少MIPS?
查看答案
Fill in each blank with a suitable preposition or adverb. (一道题有多个空,答案之间用逗号,隔开)1) Father leaves _____ work in the morning after breakfast.2) As many as 2 out of 3 marriages now end _____ divorce, leading _____ a situation where many children live _____ one parent and only see the other at weekends or holidays.3) Some people have blamed this increase _____ the rise in crime.4) As _____ children themselves, some argue that modern children grow up more independent and mature than in the past.5) They are used to dealing _____ strangers and mixing with other children.6) He will be entirely responsible _____ her financial support, and she _____ the running of the new home.7) When British people say that their society is based _____ family life, they are thinking of “family” ______ its narrow, peculiarly European sense of mother, father and children living together alone in their own house as an economic and social unit.8)For both the man and the woman, marriage means leaving one’s parents and starting one’s own life. The man’s first duty will then be ____ his wife, and the wife’s ____ her husband.
酵母克隆载体YEp 、YIp、YRp三者的稳定性关系为( )。
A. YEp>YRp>YIp
B. YIp>YEp>YRp
C. YRp >YEp>YIp
D. YIp> YRp > YEp
pYAC3是典型的酵母人工染色体,下面哪一项不属于这个人工染色体的组分( )。
A. URA3
B. CEN4
C. TEL
D. LacZ
外源DNA的转化过程中,不属于直接转化法有:( )。
A. 基因枪法
B. 电激法
C. PEG介导法
D. 农杆菌介导法