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【简答题】
已知实数 x 、 y 满足 x 2 + y 2 +2 x －2 y =0，求 x + y 的最小值.
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皮皮学刷刷变学霸
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【单选题】I didn’t sleep well last night because of the noise. It was not until midnight ___ the noise in the street stopped.
A.
that
B.
when
C.
since
D.
at which
【单选题】I didn’t sleep well last night because it was too _______ outside.
A.
noisy
B.
quiet
C.
noise
D.
Loud
【单选题】I didn’t sleep well ________ the noise from that factory nearby.
A.
because
B.
because of
C.
Unless
【单选题】—You look tired. Why? — I didn’t sleep well. The math exam is coming. —____ . I ’ ll help you.
A.
Don’t worry
B.
That’s too bad
C.
Yes
D.
Thanks
【简答题】轻型井点设备主要有井点管、弯联管、 及抽水机等组成。
【单选题】I didn’t sleep well last night as all the heating __________.
A.
went off
B.
went on
C.
went up
D.
went down
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