Hallucinogens are <span>psychoactive drugs.
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They mainly affect brain function and result in changes in behavior, mood, thinking, perception, etc.
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Answer:
A retrospective cohort study
Explanation:
A cohort study is an observational study in which individuals are classified (or selected) according to exposure status (exposed and unexposed) and followed to assess the incidence of the disease over a given period of time. Cohort studies can also be used to assess the risks and benefits of using a particular medication.
In the case of the research exposed in the question, one researcher analyzed the city's records to see who among the city's retirees had spent their careers working mostly indoors, without sun exposure; and outdoors with sun exposure. The sun is a major cause of hair cancer. Once participants were enrolled and screened, the scientist researched and examined the incidence of any form of skin cancer. This is a perfect example of a retrospective cohort study.
"Vietnam" was once a French colony, was split by war from 1954 to 1975, and currently exists as a unified, socialist state.
From 1954 to 1975, Vietnam was again partitioned into two separate countries, isolated by the Bến Hải River in Quảng Trị Province at the seventeenth parallel. The North, led by a socialist government, was aligned with comrade China and the Soviet Union, while the South had a free-advertise economy, semi fair government and had contact with the United States, the West and Western-adjusted countries. In spite of the fact that the country has been joined since 1975, phonetic, social, and different contrasts serve to outline the two locales from each other, with going with generalizations.
