wireless keyboard and wireless mouse (microsoft)

[comp builder]

hi i have just brought a wireless keyboard and wireless mouse (microsoft) and they take batteries (obviously) anyway i was wondering if when my comp is turned off are the battries in my keyboard and mouse stil running (i think they are but just enquiring) and does anyone know how long these batteries normally last for?
thanks

 

[comp builder]

thanks guys i was gunna get recharbles but i thought i might aswell use the ones that were supplied with the keyboard and mouse and then buy recharbles when they are dead lol
thanks

 

[comp builder]

ok im going to buy some recharbles for it when these run out, does anyone know why the keyboard battries last longer than the mouse batteries?
i thought it would have been the other way around because the keyboard is bigger with more buttons lol
thanks

 

[comp builder]

oooo yeh of course thanks for the help guys i really apreciate it
thanks again