如图，l1反映了某公司产品的销售收入与销售量的关系，l2反映了该公司产品的销售成本与销售量的关系，根据图意填空：x/吨y/元O123456100040005000200030006000l1l2(1)当销售量为2t时，销售收入＝元，销售成本＝元；20003000x/吨y/元O123456100040005000200030006000l1l2(2)当销售量为6t时，销售收入＝________元，销售成本＝_______元；60005000(3)当销售量为时，销售收入等于销售成本；4tx/吨y/元O123456100040005000200030006000l1l2(4)当销售量时，该公司赢利(收入大于成本)；当销售量时，该公司亏损(收入小于成本)；大于4吨小于4吨x/吨y/元O123456100040005000200030006000l1l2x/吨y/元O123456100040005000200030006000l1l2(5)l1对应的函数表达式是，l2对应的函数表达式是______________.y＝1000xy＝500x＋2000
