Three. One to hold the light bulb and two to spin the ladder.
Only one, but it takes nine years.
None. Light bulbs don't change anything.
It takes two. One to change the bulb and the other to kick the switch.
We can see no need for uninstallation and have therefore made no provision for light bulbs to be removed.
He couldn't figure out how to refill the hand dryer!
She was afraid someone would steal her IP address.