Answer:
I believe the answer to this question is b observable physical evidence.
Explanation:
The reason for this is because scientists make predictions and use evidence to back up their hypothesis. If the evidence doesn't support their claim, they make up a new one, until they have gathered enough evidence to support their claim. This can be done through past knowledge, like failures and successes and lab experiments, so it is not only each of them, so the answer cannot be c or d. Out of the two options, a and b, I just thought about it and picked b as the reasonable answer. Please give me feedback on the answer, if it is right or not. Thanks! Hope I helped!
Answer:
C.
It controls the entry and exit of substances.
Answer:
to provide structure and some fuel
Explanation:
yes sir
Answer:
the language.. please express in English
