(-3)³+5²-(-2)²
=-27+25-4
=25-(27+4)
=25-31
=-6
-8÷(-4又1/2)÷(-2又2/3)
=-8÷(-9/2)÷(-8/3)
=-8×(-2/9)×(-3/8)
=-(8×2/9×3/8)
=-2/3（-6）÷[（-5分之2）÷（-4分之1）]（-0.25）×3.14×40最后两道 ，写完个采纳！！(-6)÷[(-2/5)÷(-1/4)]=-6÷[(-2/5)×(-4)]=-6÷[(2/5)×4]=-6÷8/5=-6×5/8=-15/4 (-0.25)×3.14×40=-0.25×40×3.14=-(0.25×40×3.14)=-31.4