Answer and Explanation:
Observing population directly gives you accurate result .
Direct observation does not need any intermediary as they themselves go for survey.
So, it is cost efficient.
Whereas indirect observing may involve manipulations.
It requires someone or many to hire who helps in surveying.
It incurs cost.
Thus, direct observation is always better than indirect observation.
All of the above is the answer.
a cell adapts using natural celection in the long term
in the short term, look at this Wikipedia article.
https://en.wikipedia.org/wiki/Cellular_adaptation
Answer is B.
Antagonist is a drug that blocks the action of the neurotransmitter.
Hope it helped you.
-Charlie
