2 years old.
Cow: "Mooooove over"
Sheep: "Naaaaaaa."
or
Two. One to assume the ladder and one to change the bulb.
A': None. If the government would just leave it alone, it would screw itself in.
or
Five. One to screw it in and four to tell him how bitchin' he looked doing it.
or
Because it gave him a big wave!
or