计算 (1)-9+12-3+8 (2)(-1)+(-)+(+)-(+) (3)(-3)÷2÷(-3)×(-0.75) (4)-16-(1-0.5)××[2-(-3)2]
计算:.
计算:
计算:.
计算:(π-3.14)+ 2-()+︱-2010 ︱