3. what advantages do these geese have
by traveling in a large group?
a. they are hidden from predators.
b. they can fly slower.
c. they can cope with a changing
environment.
d. they won't fall out of the sky.

An ecosystem is in a certain area and includes living and non living plus there is weather conditions and a biome is a large amount of area with similar climate.so ecosystem is based on weather and biome is based on the average climate 

Dnaa living organsimcreation from organic chemicals

Yes yes yes very good