How would results vary between observing a population directly as opposed to observing them indirectly?

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.

On the subjects, direct observation can be made by noticing the behaviors they possess in their natural habitat. In order to gather the information, the investigator can either hide to prevent any intrusion or can be either present physically to record the observations with the help of a camera. For example, recording or watching a chirping bird.  

On the other hand, indirect observation comprises recording of the traces left behind by the subject to comprehend the cause behind the behavior demonstrated by the subject. For example, recording the distribution of the bird droppings to determine their movement.  

Therefore, it can be concluded that direct observation helps in determining the behavior in a population and an indirect observation will assist in developing the cause behind the witnessed behaviors in the population.  

the answer is c) abandoned properties that are contaminated with hazardous materials.