b)[434:14-(5608:8+924:33):27]:2-1=
=[31-(701+28):27]:2-1=
=[31-729:27]:2-1=
=(31-27):2-1=
=4:2-1=
=2-1=1
c)71+5x[100-2x(306:9+6)]+54:6x21=
=71+5x[100-2x(34+6)]+8x21=
=239+5x(100-2x40)=
=239+5x20+168=
=239+100+168=
=507
d)[520:10-7x(3+18:9)]x5+6x(15x12-15-10):15
=
=[52-7x(3+2)]x5+6x(180-25):15
=
=(52-7x5)x5+(6x155):15
=
=(52-35)x5+930:15
=
=14x5+62
=
=70+62=132