It is a weatherathorosist.
The entire group that the researcher is interested in is called the population or the target population.
A Medical researcher.
the dependent varible
A person who studies marijuana is called a cannabis researcher or a cannabinoid researcher.
The entire group that a researcher is interested in is called the population. This includes all individuals who meet the criteria for the study and about whom the researcher wants to draw conclusions.
An observational study.
sample
Either: A Cancer Researcher A Researcher A Scientist
scientist doctor physicist researcher experimenter
The variable that the researcher intentionally changes in a scientific experiment is called the independent variable. This variable is manipulated by the researcher to observe its effect on the dependent variable.
the populas
I believe what you're referring to is a double blind study. Where neither the researcher or the subjects know who has the placebo and who does not.