单位定期存款起存金额为人民币（）。A.1000元 B.5000元 C.10000元

高粱、玉米和薯类等经过发酵、蒸馏，可得到乙醇，乙醇属于______能源，俗称______，化学式为______，完全燃烧的化学方程式为______，如若在汽油中加入适量的______作为汽车燃料，可节省______，促进______，也可减少______．

下列实验操作正确的是[ ]

A.

B.

C.

D.

屋脊棱镜是一种变形的直角棱镜，其斜面由两个构成90°角的屋脊反射面所代替。( )

碧螺春茶主要产于（）。

A.黄山毛峰

B.杭州甜湖

C.江苏太湖洞庭山

D.河南信阳

Until recently, most population growth has occurred in relatively dense urban environments. In (91) words, even if we were witnessing rapid population growth, that would not mean that the (92) were filling in with people. (93) , the urban areas would tend to become more crowded. Historically, we find that people have moved to (94) the jobs were. Jobs were usually in ports or locations with many natural (95) . After transportation became relatively cheap, other geographical locations became (96) of economic activity. One factor that determines where people will move to, even when transportation becomes cheap, is (97) . And individuals working in cities (98) higher incomes than those working in (99) areas. Hence, population has tended until the 1970s to (100) in our major urban centers. Recently population has (101) out of the Northeast to the South and to the West for the more pleasant climates. If people did not (102) from living in large cities, there would likely be a much more even population distribution (103) our entire land area. Probably, if this (104) the case, there would be less concern over population (105) Indeed, one need only (106) a cross-country drive or plane trip to realize how (107) populated these United States really are. This is not to say that we should or should not do something about (108) growth. The shortage of people in certain areas merely demonstrates that overpopulation in the United States is really only a problem in (109) urban environments. And this problem may be slowly correcting (110) .

A．profit

B．expense

C．income

D．deposit