主题：判断公式 表达式中存在语法错误

if(([TFe]>=64.5)and([SiO2]<=8.00)and([CaO]>=1.00)and([S]<=0.30)and([P]<=0.25)and([H2O]<=7.0),"一级",if(([TFe]>=63.00)and([SiO2]<=10.00)and([CaO]>=1.00)and([S]<=0.30)and([P]<=0.25)and([H2O]<=10.0),"二级",if(([TFe]>=60.00)and([SiO2]<=12.50)and([CaO]>=1.50)and([S]<=0.40)and([P]<=0.30)and([H2O]<=10.0),"三级",if(([TFe]<60.00)and([SiO2]>12.50)and([CaO]<1.50)and([S]>0.40)and([P]>0.30)and([H2O]>10.0),"不合格",))))

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