确认population和sample

问题描述:

确认population和sample
A sociologist obtains a list of 520 members of a local business and professional women's club and mails a questionnaire to 100 of these women selected random.Only 48 questionnaries are returned.What is the poopulation in this study?what is the sample from whom iinformation is actually obtained?

population is 520
the sample size is 100
information is actually obtained from 48 people