Answer:
d. cross-sectional study
Explanation:
In research, a cross-sectional study consists of a gathering of data from a population or a subset of the population we want to investigate at an specific point of time. In other words, the data will give us an idea of what's happening within a group in a particular moment in time.
In this example, the researcher gives 20-year-olds, 40-year-olds, and 60-year-olds a questionnaire. He wants to know if older people are calmer than younger ones. We can see that <u>he wants to know what's happening within this groups (the 20 year-olds, the 40's and the 60's) during this particular time of their life </u>and therefore determine if the 60 year-olds are calmer. Therefore this is an example of cross-sectional study.
<span>A natural monopoly is a type of monopoly that exists as a result of the high fixed costs or startup costs of operating a business in a specific industry. Additionally, natural monopolies can arise in industries that require unique raw materials, technology or other similar factors to operate.</span>
The correct answer to this open question is the following.
The impact of the commercial revolution (16th century ) in Western Europe was the following.
The commercial revolution's impact was that it generated a big competence between European countries in trade. The rules of trade and commerce dramatically changed due to the Columbian exchange and all the goods, raw materials, and natural resources were affected due to this competence between European nations, supply, and demand.
The commercial revolution also saw the beginning of financial institutions and the surge of banking institutions that coined money and made loans.
The current president of India is Pranab Mukherjee, a Bengali politician from the Indian National Congress. He came to this office in 2012.
Dopamine makes us look for, want, and search. Dopamine is invigorated by unusualness, by little pieces of data, and by remuneration prompts essentially the specific states of virtual entertainment.
<h3>
What does Human psychology means?</h3>
Among the significant objectives of brain science are to depict, make sense of, foresee, and work on human way of behaving.
Human Psychology is the study of brain and human way of behaving. The overall definition might allude to the calling, additionally alluded to as clinical psychology; the insightful discipline, alluded to as scholarly psychology or instructive psychology; or the logical pursuit, research.
Therefore the logical investigation of all types of human and creature conduct, in some cases worried about the strategies through which conduct can be changed.
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