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【简答题】
用图所示的装置来测滑轮组的机械效率． （1）实验要求，用弹簧测力计拉动绳端时，拉力的方向应______，并使物体______上升． （2）若弹簧测力计移动15cm，则物体移动______cm． （3）若被提升的物体是钩码，每只钩码重为2N，每只滑轮重为0.5N，弹簧测力计读数是2.5N，则拉力做的额外功是______．滑轮组的机械效率是______． （4）若再加挂一只钩码重做实验，所测的机械效率与前一次相比将______．（选填“相同”或“变大”“‘变小”）
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【简答题】At school many things happen to us. We may feel excited when we have success in a school play. We may feel sorry if we lose an important . We want to keep the memory for the rest of our lives. Ho...
【单选题】We began to enter into a__________ (success) partnership with them last year.
A.
success
B.
B . succe ed
C.
successfully
D.
successful
【简答题】[A] a large number of [B] the large number [C] a larger number of [D] the larger number of
【简答题】We began to enter into a____________ (success) partnership with them last year.
【单选题】If you want to do business with Russian companie
A.
you must understand Russian.
B.
you need to entertain your hosts, because the Russians like having fun.
C.
you need to make time for social and cultural events.
【单选题】In his line “Let the word go forth from this time and place” , the word means ____
A.
the word from the Bible
B.
the word from God
C.
Kennedy’s word
D.
the forefather’s word
【单选题】—What's your ________? —I'm ________? [ ]
A.
number; number 3
B.
number 3; number
C.
number; Number 3
D.
Number; Number 3
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