Prime Factorization: Recognizing divisibility rules

I am a two-digit number $?0$

Which prime factor will surely appear among my first factors?

$2$

I am a two-digit number $?0$

Which prime factor will surely appear among my first factors?

$5$

I am a two-digit number $?4$

Which prime factor will surely appear among my first factors?

$2$

I am a three-digit number $?12$

Which prime factor will surely appear among my first factors?

$2$

I am a three-digit number $3?0$

Which prime factor will surely appear among my first factors?

$5$

I am a three-digit number $?50$

Which prime factor will surely appear among my first factors?

$2$

I am a three-digit number $??5$

Which prime factor will surely appear among my first factors?

$5$