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某月食品加工厂以2万元引进一条新的生产加工线.已知加工这种食品的成本价每袋20元,物价部门规定:该食品的市场销售价不得高于每袋35元,若该食品的月销售量y(千袋)与销售单价x(元)之间的函数关系为:y=
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(月获利=月销售收入﹣生产成本﹣投资成本).
(1)当销售单价定位25元时,该食品加工厂的月销量为多少千袋;
(2)求该加工厂的月获利M(千元)与销售单价x(元)之间的函数关系式;
(3)求销售单价范围在30<x≤35时,该加工厂是盈利还是亏损?若盈利,求出最大利润;若亏损,最小亏损是多少.