提成=销售额*销售提成系数 销售提成系数比例:达标率≤60% ,提成系数2%,60%<个人达标率≤75%,提成系数2.3%,75%<个人达标率≤85%,提成系数2.6%,85%<个人达标率≤100%,提成系数3%,100%<个人达标率,提成系数3.5%例:销售额252500 ,达标率120%。请问如何运用函数计算公式???