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In recent years a new farming revolution has begun, one that involves the (21) of life at a fundamental level — the gene. The study of genetics has (22) a new industry called biotechnology. As the name suggests, it (23) biology and modem technology through such techniques as genetic engineering. Some of the new biotech companies specialize (24) agriculture and are working feverishly to duplicate seeds that give a high yield, that (25) diseases, drought and frost, and that reduce the need for (26) chemicals. (27) such goals could be achieved, it would be most beneficial. But some have raised concerns about genetically engineered crops. In nature, genetic diversity is created within certain space. A rose (28) be crossed with a different kind of rose, but a rose will never cross with a potato. Genetic engineering, (29) , usually involves taking genes from one species and inserting them into (30) in an attempt to transfer a desired characteristic. This could mean, (31) , selecting a gene which leads to the production of a chemical with anti-freeze quality from an arc- tic fish, and inserting (32) into a potato or strawberry to make it frost-resistant. In essence, then, biotechnology allows humans to (33) the genetic walls that separate species. Like the green revolution, (34) some call the gene revolution contributes to the problem of genetic uniformity — some say even more so that geneticists can employ techniques (35) as cloning and (36) culture, processes that produce perfectly (37) copies. Concerns about the erosion of biodiversity, therefore, (38) . Genetically altered plants, however, raise new issues, such as the effects that they may have (39) us and the environment. "We are flying blindly into a new era of agricultural biotechnology with high hopes, few constraints, and (40) idea of the potential outcomes," said science writer Jeremy Rifkin.

A. what
B. as
C. where
D. so

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设d是线性方程组AX=b的解,β1,β2,…,βt是其导出组的基础解系,令 γ1=α+β1,γ2=α+β2,…,γt=α+βt 试证: 方程组Ax=b的任一解γ可表示为γ=l0α+l1γ1+l2γ2+…+ltγt,其中l0+l1+…+lt=1.

设d是线性方程组AX=b的解,β1,β2,…,βt是其导出组的基础解系,令 γ1=α+β1,γ2=α+β2,…,γt=α+βt 试证: α,γ1,γ2,…,γt线性无关;

向量组β1=(0,1,-1)T,β2=(x,2,1)T,β3=(y,1,0)T与向量组α1=(1,2,-3)T,α2=(3,0,1)T,α3=(9,6,-7)T有相同的秩,且β3可由α1,α2,α3线性表示,则x,y的值为______

A. x=12,y=4
B. x=15,y=5
C. x=-12,y=-4
D. x=-15,y=-5

三、根据以下资料,回答116~120题。 2013年3月末,金融机构人民币各种贷款余额65.76万亿元,同比增长14.9%,增速比上年同期低0.8个百分点。 2013年3月末,主要金融机构及小型农村金融机构、外资银行人民币小微企业贷款余额11.78万亿元,同比增长13.5%,比全部企业贷款余额增速高1.2个百分点。 2013年3月末,主要金融机构本外币工业中长期贷款余额6.46万亿元,同比增长3.2%。其中,轻工业中长期贷款余额6824亿元,同比增长7.6%;重工业中长期贷款余额5.77万元,同比增长2.7%。服务业中长期贷款余额16.55万亿元,同比增长8.9%。 2013年3月末,主要金融机构及小型农村金额机构、村镇银行、财务公司本外币农村贷款余额15.24万亿元,同比增长18.4%;农户贷款余额3.86万亿元,同比增长16.9%;农业代款余额2.87万亿元,同比增长12.3%。 2013年3月末,主要金融机构及小型农村金融机构、外资银行人民币房地产贷款余额12.98万亿元,同比增长16.4%。地产开发贷款余额1.04万亿元,同比增长21.4%。房产开发贷款余额3.2万亿元,同比增长12.3%。个人购房贷款余额8.57万亿元,同比增长17.4%。保障性住房开发贷款余额6140亿元,同比增长42.4%。 2013年3月末,各项贷款余额从高到低排序正确的是:

A. 农户贷款余额 地产开发贷款余额 农业贷款余额
B. 房产开发贷款余额 地产开发贷款余额 轻工业中长期贷款余额
C. 服务业中长期贷款余额 农户贷款余额 重工业中长期贷款余额
D. 重工业中长期贷款余额 轻工业中长期贷款余额 房产开发贷款余额

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