制作某书橱需木材为0.036m3,若配料时,损耗率为25%,当制作120件书橱时,则需要多少木料
参考答案:V=0.036×120×1.25=5.4(m3) 需要5.4m3的木料。
* * 后壁脱垂的最主要原因()
A.产伤
B.妇科手术
C.腹压增加
D.盆底组织发育不良
E.盆底组织退行性变
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.quality
B.reduction
C.explosion
D.structure