3)-9/5*(7/2m-5)-13/2*(4/5-2/5m)=-1/10*(18(7/2m-5)+65(4/5-2/5m))=-1/10*(63m-90+52-26m)=-1/10*(37m-38)
4)4/9*(3/2c-3/8)-(11/6-4/3c)=4/9*(3/2c-3/8)-1/6*(11-8c)=1/18*(8(3/2c-3/8)-3(11-8c))=1/18*(12c-3-33+24c)=1/18*(36c-36)=1/18*36(c-1)=36*1/18*(c-1)=36/18*(c-1)