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.
Answer: What roses are the best flowers is a non-scientific question.
Explanation: What flower is better is determined by personal opinion. I might think the red roses are prettier and you might think the white ones are. Where all the other questions can be tested all equally and it is not an opinion.
Mixture should be the answer.
Secondary succession happens more often because it occurs after some kind of distribution that still leaves the soil intact (mudslide,bulldozing,shoveling,or scraping off an area)
