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【单选题】
Organic Food Organic farming was among the fastest growing segments of U.S. agriculture during the 1990s. The value of retail sales of organic food was estimated to be $16 billion in 2004. According to the Food Marketing Institute, more than half of Americans now buy organic food at least once a month. Why is organic food becoming so popular? What is Organic Food? In December 2000, the National Organic Standards Board of the U.S. Department of Agriculture (USDA) established a national standard for the term 'organic.' Organic food, defined by how it can not be made rather than how it can be made, must be produced without the use of sewer-sludge(淤泥) fertilizers, most synthetic fertilizers and pesticides, genetic engineering (biotechnology), growth hormones, irradiation and antibiotics. A variety of agricultural products can be produced organically, including produce, grains, meat, dairy, eggs, and processed food products. Organic Farming The phrase 'organic farming' first appeared in Lord Northbourne's book 'Look to the Land,' published in 1940. But the truth is, organic farming is the oldest form. of agriculture. Before the end of World War II, farming without the use of petroleum-based chemicals (synthetic fertilizers and pesticides) was the only option for farmers. Technologies developed during the war were found to be useful for agricultural production. For example, the chemical ammonium nitrate(硝酸钠氨), which was used as military supplies, became useful as fertilizer, and organophosphates(有机磷酸酯)used for nerve gas were later used as insecticide. These days, farmers are switching to organic agriculture once again, but now with an ecologically based, systematic approach that includes long-term planning, detailed record keeping and major investment in equipment and supplies. Although it is still only a small industry, the number of organic farmers is growing by about 12 percent per year and now stands at more than 12,000 nationwide. Organic Farming in the U.S. Today The USDA's Economic Research Service reports that in 1997, the latest year for which data are available, farmers in 49 states used organic production methods and third-party organic certification services on 1.35 million acres out of a total of 828 million acres of farmland. Approximately two-thirds of the certified U.S. organic farmland was used for crops, and one-third was used as pasture. Large farms, mostly located in the Midwest and West, produced processed tomatoes, organic wine grapes and other high-value crops on a commercial scale, whereas numerous small farms, concentrated in the Northeast, specialized in mixed vegetable production for direct marketing to consumers and restaurants. While organic food can be found throughout the country, California was the leader in production of organic fruits and vegetables in 1997, followed closely by Arizona, Florida, Texas, and Washington in decreasing order of total yield. Farmers and ranchers in 23 states raised a small number of certified organic cows, hogs and sheep. New York, Wisconsin and Minnesota were the top producers of organic dairy cows. Production: Organic vs. Conventional As you can imagine, organic agricultural practices are quite distinct from those of 'conventional' farming. Conventional farmers: Apply chemical fertilizers to the soil to grow their crops. Spray with insecticides to protect crops from pests and disease. Use synthetic herbicides to control weed growth. Organic farmers: Feed soil and build soil matter with natural fertilizer to grow their crops. Use insect predators, mating disruption, traps and barriers to protect crops from pests and disease. Make use of crop rotation, mechanical tillage and ha
A.
Y
B.
N
C.
NG
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皮皮学刷刷变学霸
举一反三
【单选题】长期债券投资的目的是:
A.
合理利用暂时闲置的资金
B.
调节现金余额
C.
获得稳定收益
D.
获得企业的控制权
【单选题】胆汁是一种很重要的消化液,关于胆汁的说法正确的是(  )
A.
胆汁具有将脂肪消化为甘油和脂肪酸的作用
B.
胆汁中含有脂肪酶
C.
胆汁对脂肪具有乳化作用
D.
胆汁是由胆囊分泌的一种消化液
【单选题】“一生二,二生三,三生万物;地法天,天法道,道法自然。”联语都是出自( )。
A.
《老子》
B.
《庄子》
C.
《论语》
D.
《大学》
【单选题】找出画线处读音与其他三个选项不同的单词。
A.
wave
B.
save
C.
have
D.
gave
【单选题】找出画线处读音与其他三个选项不同的单词
A.
l e sson
B.
qu e stion
C.
r e cent
D.
s e veral
【单选题】关于学校和学生,下列表述正确的是( )。
A.
在未成年学生上学期间,学校是学生的监护人
B.
学校对在校学生负有教育、管理和保护的职责
C.
发生学生伤害事故时,学校有义务垫付全部医疗费
D.
学校学生伤害事故负有责任的,应当负责解决伤害学生的户口、住房、就业等事项
【单选题】“一生二,二生三,三生万物;地法天,天法道,道法自然。”这是哪一座道教名山的对联?
A.
武当山
B.
齐云山
C.
龙虎山
D.
青城山
【单选题】“芳林新叶催旧叶,流水前波让后波”,“沉舟侧畔千帆过,病树前头万木春”。这两句诗包含的哲学道理是:
A.
矛盾是事物发展的源泉和动力
B.
事物的发展是有量变到质变的过程
C.
新事物代替旧事物是事物发展的必然趋势
D.
事物是本质和现象的统一
【单选题】长期债券投资的目的是( )
A.
合理利用暂时闲置的资金
B.
获得稳定收益
C.
获得企业的控制权
D.
调节现金余额
【单选题】样式表定义.outer {background-color:red}表示( )。
A.
网页中某一个id为outer的元素的背景色是红色的
B.
网页中含有class=”outer”元素的背景色是红色的
C.
网页中元素名为outer元素的背景色是红色的
D.
其余选项都可以
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