接触粉尘1～2年发生的硅沉着病，属何种硅沉着病A.硅沉着病B.晚发性硅沉着病C.硅酸盐肺D.肺尘埃沉着

Tom was very lucky______with his life: he almost did not get out of the room.

A．escaping

B．to escape

C．to have escaped

D．to be escaping

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Betty is the only one of the students who______to represent the group.

A．have been chosen

B．has been chosen

C．have chosen

D．has chosen

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对k个处理组，b个随机区组的资料进行方差分析，其误差的自由度为

A、kb-k-b

B、kb-k-b-1

C、kb-k-b-2

D、kb-k-b+1

E、kb-k-b+2

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自然通风气流上升式烤房处于密闭状态时，传热的方式主要是热辐射,烤房的气流()。

A.向上运动速度较慢

B.向上运动速度较快

C.大部分热空气在烟层以下空间旋转循环

D.少量热空气透过烟层传热做功

此题为多项选择题。请帮忙给出正确答案和分析，谢谢！

Odd______it sounds, cosmic inflation is a scientifically plausible consequence of some respected ideas in elementary particle physics.

A．although

B．though

C．since

D．because

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