Find how many five-digit numbers can be made using the digits $2,3,4,5$ and $6$ once each if:

there are no restrictions

Find how many five-digit numbers can be made using the digits $2,3,4,5$ and $6$ once each if:

the five-digit number must be odd.

Find how many five-digit numbers can be made using the digits $2,3,4,5$ and $6$ once each if:

the five-digit number must be even.

Find how many five-digit numbers can be made using the digits $2,3,4,5$ and $6$ once each if:

the five-digit number must be odd and less than $40000.$

Find how many ways four men and two women can stand in a line if:

the two women must be at the front.

Find how many ways four men and two women can stand in a line if:

there must be a woman at the front and a man at the back.

Find how many ways four men and two women can stand in a line if:

the two women must be separated

Find how many ways four men and two women can stand in a line if:

the four men must not be separated

[Enter the value in $m:n$ format, where $m \& n$ are smallest possible positive integers]