Researchers might use when providing participants with the full details of the experiment could skew their responses.
informed consent
deception
ethics
debriefing

this is a pretty broad question and can be a pretty lengthy answer. since 1900, women have gained a lot more rights and have become active in the workforce. with women being in the workforce, men play a larger role in family life. many family tasks are shared between men and women, whereas, women used to be the sole family caretakers.

that should get you started at least.

answer; i believe its (transgender);

answer; 55-85;

representative sample

sociologists study the world, observe a predicament or interesting design, and set out to investigate it. they use investigation methods to design a study possibly a comprehensive, detailed and precise, by using experimental method for directing research and gathering data.

to study the characteristics of the whole population, sociologist prefers to obtain the sample which is the finite part of a demographic population whose characteristics are analyzed to obtain data from statistics.

when administering with population, it can be described as a set of respondents picked from a larger population for the goal of a survey. a population could be a group of objects, people, or articles from which samples are obtained for computation of the whole population which is the aim of the sociological study.