Answer to Question 1
sampling frame
Answer to Question 2
Mail questionnaires - Advantages are easy, inexpensive, cover a wide geographical area, can be done at respondents convenience, anonymity and limit interviewer bias. Disadvantages are low response rate, people who respond are not representative, no control over conditions of completion, limits types of questions.
Telephone - Advantages are can reach about 95 of population by phone, use of random-digit dialing, wide geographical area, short turn-around time, can use probes. Disadvantages are higher cost, limited interview length, respondent is not available by phone, potential interviewer bias Face-to-face - Advantages are highest response rates and longest questionnaires, interviews can observe nonverbal communication, extensive probes. Disadvantages are training, travel supervision and personnel costs of interviews, interviewer bias, limited geographical area. Web survey - Advantages ae lowest cost, quick answers, span geographic areas and include visual media. Disadvantages are that not everyone has computer or internet access, low response rate,
can't control conditions under which the respondent takes the survey.
Lambda phage inserts by a crossover at a specific site
Potential applications of embryonic and tissue specific adult stem cell in cellular and gene theraph
How Fast is the World's Population Growing?
Hypersensitivity reactions and different target organs.
A very small sampling of organisms in an arctic food web on land.
A Short List of Human X-Linked Recessive and X-Linked Dominant Traitsa