`a, = (2004-4)(2004+4)
`= 2000 . 2008`
`= 4016000`
`b, = (85+15)^2`
`= 10000`
`c, = (892 + 108)^2`
`= 1000^2`
`= 1000000`
`d, = (36-26)^2`
`= 100`
`a, = (2004-4)(2004+4)
=2000.2008=2000.2008
=4016000=4016000
b,=(85+15)2b,=(85+15)2
=10000=10000
c,=(892+108)2c,=(892+108)2
=10002=10002
=1000000=1000000
d,=(36−26)2d,=(36-26)2
=100