In recent years a new farming revolution has begun, one that involves the (61) of life at a fundamental level--the gene. The study of genetics has (62) a new industry called biotechnology. As the name suggests, It (63) biology and modern technology through such techniques as genetic engineering. Some of the new biotech companies specialize in agriculture and are working feverishly to (64) seeds that give a high yield, that (65) diseases, drought and frost, and that reduce the need for (66) chemicals. If such goals could be achieved, it would be most (67) . But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain (68) . A rose can be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (69) usually involves taking genes from one species and inserting them into another (70) to transfer a desired characteristic. This could mean, for example, selecting a gene which leads to the production of a chemical with anti-freeze (71) from an artic fish, and inserting it into a potato or strawberry to make it frost-resistant. (72) , then, biotechnology allows humans to (73) the genetic wails that separate species. Like the green revolution, (74) some call the gene revolution contributes to the problem of genetic uniformity--some say even more so (75) geneticists can employ techniques such as cloning and (76) culture (培养), processes that produce perfectly (77) copies. Concerns about the erosion of biodiversity, therefore, remain. Genetically altered plants, however, raise new (78) , such as the effects that they may have on us and the environment. "We are flying blindly into a new (79) of agricultural biotechnology with high hopes, few constraints, and little idea of the potential (80) " said science writer Jeremy Rifkin.
A. hazardous
B. hydraulic
C. hostile
D. harmless
(二)某土地估价机构于2006年10月下旬接到一宗土地价格评估的委托,估价基准日确定在当年10月31日。评估对象位于华南K城市的S湖边,面积500m2,是委托方于2000年10月通过拍卖方式购得的土地,使用期限50年。目前该地块内有一座900m2砖混结构的写字楼,建于2002年10月。写字楼现用于出租,每月租金收入3万元。市场调查显示,该类房屋耐用年限为55年,残值率为2%,当时建筑物综合造价为2000元/m2,目前重置价格为2500元/m2。该写字楼的利用率为90%。当地同类写字楼出租正常空置率为10%,租金一般为每月50元/建筑m2,每年需支付的总费用约80元/建筑m2。假定土地还原率和房屋卒原率分别为7%和8%。根据上述情况,计算并回答56~60题。 如果其他条件不变,假定土地的纯收益为50万元,则土地总价格为()万元。
A. 648
B. 658
C. 678
D. 698