Answer 1

!(a&&b) would be true, as they don't match in value or should I say boolean value. If a and b were both true values, then it would false.

Answer 2

reuslt is true because the follwing
(&& and) operator: let's know the truth table of it and when the value will be true or false
a | b | result
true true true
true false false
false true false
false false false
so a and b both have to be true to make the reuslt true and here a is true and b is false then the result is false but there is a (!not) operator and it will reverse the value
so true will be false and false will be true
then final result is true