用简便方法计算下面各题(18分)
(1)13.6－1.8－3.2                (2)13.7＋1.98＋0.02＋5.3
(3)5.1＋0.9－5.1＋0.9             (4)36×99
(5)10.75＋0.4＋0.25              (6)38.14－5.46－4.54