25 of them.
30
There is one prime number between 90 and 100. It is 97.
54, 63, 72, 81, 90, 99.
49,200
It is 2 which also is the only even prime number
1, 2, 4
billions
30
4962 but i could b wrong as my hand got sore so the number could b a bit off
79.
It is: 1
1
1 and 5
There are no factors of 10 between 20 and 100.
One and five.
One of them.