tính hợp lý
a)5.(-3)^2-14.(-8)+(-40)
b)31-[26-(209+35)]
c)237+26-(209+26)
d)21+22+23+24-11-12-13-14
e)(-12).46-12.54
g)(-8).25.(-2).4.(-5).125
h)(-50+19+143)-(-79+25+48)
i)(-37-17).(-9)+35.(-9-11)
k)512.(2-128)-128.(-512)
l)160:{|-17|+[3^2.5-(14+2^11:2^8)]
m)|-6|+(-17)+|-4|+(-3)
n)5^6:5^3-5^0.5^1.5^2
o)100:{31-[24:(18-7.2)]}
k)