A.(8.28+2.69)+4.72 =(8.28+4.72)+2.69 =13+2.69 =15.69B.(8.28+2.69)+4.72 =8.28+2.69+4.72 =10.97+4.72 =15.69C.(8.28+2.69)+4.72 =2.69+8.28+4.72 =2.69+13 =15.69