Va roggg am nevoie mare

a)879+363:11-25·36=
=879+33-900
=912-900=12
b)16·16-975:75-9·27=
=256-13-243
=243-243=0
c)15·18-490:70-261=
=270-7-261
=263-261=2
d)56·72:126+222-88=
=4032:126+222-88
=32+222-88
=254-88=166