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【简答题】
一项工程，甲单独完成要9天，乙单独完成要12天，丙单独完成要15天．若甲、丙先做3天后，甲因故离开，由乙接替甲的工作，问：还要多少天能完成这项工程的 ？
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【单选题】听力原文：M: Belinda, the will begin soon. W: I can't wait to watch the , Martin. This is the first time I've ever been to a soccer at a stadium. I always watch them on TV at home. M: This is...
A.
It is exciting.
B.
It is violent.
C.
It is crazy.
D.
It is hard.
【单选题】听力原文：M: Belinda, the will begin soon. W: I can't wait to watch the , Martin. This is the first time I've ever been to a soccer at a stadium. I always watch them on TV at home. M: This is...
A.
It is exciting.
B.
It is violent.
C.
It is crazy.
D.
It is hard.
【简答题】正常瞳孔在自然光线下直径约 ()，瞳孔直径大于()称瞳孔散大，瞳孔直径小于()称瞳孔缩小。
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