How is 1996 * 2000-2000 * 1996 1996 the easiest

How is 1996 * 2000-2000 * 1996 1996 the easiest

1996*20002000-2000*19961996
=1996*2000*10001-2000*1996*10001
=0

Calculation: 20112011 × 2011-20112010-20112010 × 2010=______ ．

20112011 × 2011-20112010-20112010 × 2010, = 20112011 × 2011 - (1 + 2010), = 20112011 × 2011-20112010 × 2011, = 2011 × (21112011-20112010), = 2011 × 1, = 2011; so the answer is: 2011

2000+20002000+… +2000, 2000, 2000 20002001+20012001+… +20012001… 20012000, 2001 =___ ．

2000+20002000+… +2000, 2000, 2000 20002001+20012001+… +20012001… 2001 = 2000 × (1 + 10001 + 10001 +...) +1999 10001100010001 10001)2001×(1+10001+100010001+… +100010001… 100011999 (10001) = 2000

99999×77778+33333×66666=______ ．

99999 × 77778 + 33333 × 66666, = 99999 × 77778 + 33333 × (3 × 22222), = 99999 × 77778 + (33333 × 3) × 22222, = 99999 × 77778 + 99999 × 22222, = 99999 × (77778 + 22222), = 99999 × 100000, = 999900000