实验设计过程中研究者能人为设定 A．处理因素 B．条件因素 C．客观因素 D．实验因

拔除严重破坏的第一恒磨牙，用第二恒磨牙代替第一恒磨牙的最佳时间是（）

A.6～7岁

B.8～10岁

C.11～12岁

D.12～14岁

E.14岁以后

(2) 病灶可能在( )

A．左侧中央后回
B．右侧中央后回
C．左侧中央前回
D．右侧中央前回
E．颞叶

装药后必须保证堵塞质量，但（）可使用无堵塞爆破。

A、扩壶爆破

B、洞室爆破

C、浅孔爆破

D、深孔爆破

The wild mouflon sheep of the island of Corsica are direct descendants of sheep that escaped from domestication on the island 8,000 years ago. They therefore provide archaeologists with a picture of what some early domesticated sheep looked like, before the deliberate selective breeding that produced modem domesticated sheep began.
The argument above makes which of the following assumptions

A．The domesticated sheep of 8,000 years ago were quite dissimilar from the wild sheep of the time.

B．There are no other existing breeds of sheep that escaped from domestication at about the same time as the forebears of the mouflon.

C．Modern domesticated sheep are direct descendants of sheep that were wild 8,000 years ago.

D．Mouflon sheep are more similar to their forebears of 8,000 years ago than modem domesticated sheep are to theirs.

E．(E) The climate of Corsica has not changed at all in the last 8,000 years.

站起和坐下训练难度的提高不能通过以下哪种方式实现（）。

A、降低椅子高度

B、站起和坐下的速度保持不变，动作连续

C、与人交谈中站起和坐下

D、双手持物站起和坐下

E、加快站起和坐下的速度