计算下面各题。-j4l5K6q7P-g4V6{
（1）75＋638－438＋25-j4l5K6q7P-g4V6{
算式：提示/];v.`.~.M:P-j4l5K6q7P-g4V6{
（2）9＋99＋999＋4-j4l5K6q7P-g4V6{
算式：提示/Y9V3f;N+Y'V,w)y2[7D:G-j4l5K6q7P-g4V6{
（3）9＋98＋97＋8-j4l5K6q7P-g4V6{
算式：提示7d6V/]*g9E-j4l5K6q7P-g4V6{