A plumpkin.
or
One's a spineless, poisonous blob. The other is a form of sea life.
or
Because she wanted to hit the high C's.
or
So that real estate agents would have someone to look down on.
or
None. The darkness will cause the bulb to change by itself.
or
Twenty. One to hold the bulb, two to turn the ladder, and 17 to be on the guest list.
or
A sunburnt penguin
or
But I don't want to be naked in an exam I haven't revised for.
or
A ferrous wheel.
or
Plug its nose.
or