Answer:
Sing me to a baby about to go to sleep.
Whoever made me doesn't want me. Whoever bought me doesn't need me. Whoever uses me doesn't know me. What am I?
I can fall off a building and live, but in water I will die. What am I?
I am a busy worker who is a water mammal.
I am the noise Santa's reindeers make
What is always coming but never arrives?