Five: One to change the bulb and four to pull the ladder out from under him/her.
or
Because all his uncles were "ants"!
or
Five. Four to decide which way the bulb ought to turn, and . . .
or
2 years old.
Cow: "Mooooove over"
Sheep: "Naaaaaaa."
or
Because he wasn't peeling well!
or