`(888+777+555)=(111xx ?)`

En each of the following,fill in the blanks,so that the statements is true: (500+7)(300-1)=29x888+777+555=111x75x425=(70+5)(+85)89x(100-2)=98x(100-...)(15+5)(15-5)=225-...9x(10000+...)=98766

Find the unit digit of expression (823)^(933!) × (777)^(223!) × (838)^(123!) × (525)^(111!)

Hydrolysis constant of NH_(4)^(+) is 5.55 xx 10^(-10) . The ionisation constant of NH_(4)^(+) is

(888 xx 888 xx 888 - 222 xx 222 xx 222)/(888 xx 888 + 888 xx 222 + 222 xx 222) = ?

Find the unit digit in the expression 999 xx 888 xx 100 xx 64 xx 49 .