关于t分布，下列叙述正确的是（） A.t分布是以0为中心，σ=1的，左右对称的单峰分

The boy isn’t _______ to dress himself.

A．old enough

B．enough old

C．old

D．too young

根据所提供的句子意思，将所给单词的正确形式填空，使句子意思完整。

小题1:Do the Smiths enjoy _________ in China? (live)

小题2:Whose drawing is _________, Tom’s, yours or Jim’s? (bad)

小题3:Jim went to school in a hurry this morning without ________ breakfast. (eat)

小题4:He was a famous writer in the __________ century. (twenty)

小题5:June 1 is ____________ (child) Day.

小题6:Which of those do you think is the second useful ____________ (invent)?

小题7:Wang Hong taught________ English when she was eleven years old. (she)

小题8:My mother ________ a lot of eggs yesterday.(buy)

小题9:I hope everything goes ______(good).

小题10:In the United States, lunch __________ to students for free at school. (offer)

朱砂安神丸服法的注意事项是（）

A.宜多服

B.宜久服

C.宜饭前服

D.不宜多服、久服

E.无需禁忌

在（），列车不准分部运行。

A、遗留车辆无人看守时

B、按自动闭塞法运行时

C、遇降雾、暴风雨雪

D、电话中断后发出的列车

V3008中铬催化剂浸润用的是（）。

A.HSR

B.LSR

C.POW

D.LIR