Answer:
Weight in my belly trees on my back nails in my ribs feet I do lack.
Sometimes dark and sometimes bright, I make my way among twinkling lights. Seas and oceans obey my call, yet mountains I cannot move at all. What am I?
I rise and fall no matter what, only at finals rest do I not budge. What am I?
I am a fruit with seed on the outside. What am I?
I am a busy worker who is a water mammal.
Give it food and it will live, give it water and it will die.