25
100
Not sure what a "didget" is. It is possible to make 18 5-digit numbers.
There are 4500 such numbers.
500 or so.
With a total of 90,000 five digit numbers, we can conclude that there is 45,000 EVEN five digit numbers.
There are five such numbers.
There are 252 of them.
90000
25
4,000 even numbers, 4,000 odd numbers.
100
There are 5460 five digit numbers with a digit sum of 22.
162
There are 180 3-digit numbers divisible by five.
2240
There are 450 even three-digit integers, from 100 to 998. This excludes numbers with leading zeroes (000 to 099).