Answer:
Physical characteristics.
Explanation:
She knew what type of birds they were based on their physical characteristics.
She didn't see their nests, or see them eat, and she didn't test and analyze their genetics, so a is the correct option.
Answer:He smiles becuase he gets happy.
Explanation: because of the smell coming from the bakery.
Answer:
industrial machinery
Explanation:
it was used in almost everything and allowed people to make things easier
Because it shows the ages of the population, so we can see the parts of the place with the population that can and can't work.
Now, the way these maps show social information is: because they point out the demographical distribution about a specific sub-group in the population, its age, and its growth.
And finally, the way these maps provide environmental information is: because they allow us to see the environment of certain zones inside the map territory.