用你喜欢的方法计算.(1)83.72﹣(75﹣16.28)(2)1998+199.8+19.98+1.998+2.222(3)[4.8﹣4.8×(3.2﹣2.7)]÷0.24 (4)(18.87+18.87+18.87+18.87)×2.5.