Tính hợp lí,24.(16-5)-16.(24-5)

Tinh hop li
c,24.(16-5)-16.(24-5)
d,29.(19-13)-19(29-13)
e,31.(-18)+31(-81)-31
f,(-12).47+(-12).52+(-12)
g,13.(23+22)-3(17+28)
h,-48+48(-78)+48.(-21)