计算:(1)(-3)+(+9)(2)-20+(+3)-(-5)-(+7)(3)(-7)×(-5)-90÷(-15)(4)-102+[(-4)2+(3+32)×2]÷(-2)3.
计算:.
用简便方法计算: (1) (2)
计算:(1)23-17-(-7)+(-16);(2)-1.5+1.4-(-3.6)-4.3+(-5.2); (3)(4)