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某农场,可以全部种植水果、蔬菜、稻米、甘蔗等农作物,且产品全部供应距农场d(km...
某农场,可以全部种植水果、蔬菜、稻米、甘蔗等农作物,且产品全部供应距农场d(km)(d<200km)的中心城市,其产销资料如表:当距离d达到n(km)以上时,四种农作物中以全部种植稻米的经济效益最高.(经济效益=市场销售价值-生产成本-运输成本),则n的值为( )
项目 作物 | 水果 | 蔬菜 | 稻米 | 甘蔗 |
市场价格(元/kg) | 8 | 3 | 2 | 1 |
生产成本(元/kg) | 3 | 2 | 1 | 0.4 |
运输成本 | 0.06 | 0.02 | 0.01 | 0.01 |
单位面积相对产量(kg) | 10 | 15 | 40 | 30 |
A.50
B.60
C.100
D.120
考点分析:
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