（）switching wasinvented in the late1960s for data communications.

Throughout life，peoples brains constantly restore themselves，In the late1960s，Br

[单选题]Circuit Switching is problematic because data communications is（6.1），that i

[单选题]Circuit Switching is problematic because data communications is（6.1），that i

[试题]() switching was invented in the late 1960s for data communications.A．Frame B．Link C．Packet D．Line

Twenty years later, it was purposefully dropped to make way for "Negro." By the

[单选题]B．etween the late 1950s and the late 1970s, infant mortality in northern Africa______.A．still remained highB．fell sharplyC．was lower than that in AsiaD．rose tremendously

B ) It‘s never too late to learn . C ) It‘s not late to learn . D ) It‘s too ear

[试题]H．ow does late arriving data affect dimensions and facts? Share techniques for handling each.迟到的数据对事实表和维度表有什么影响？怎样来处理这个问题？

What’s your ______ for being late again?A. ideaB. keyC. excuseD. news

[单选题]Passage OneIn the late 1860's, industry in America grew rapidly. More factories meant more jobs. But working conditions were dangerous. Employees were forced to work as many as 16 hours a day in hot, dirty rooms. Children often worked alongside adul