Nathan wants to be sure that, in the event that he is incapable of communicating, no life support will be used, even if doctors want to keep him alive. he also wants to give his wife the legal right to speak for him in that situation. in order to do all this with one document, nathan should complete a(n):
a. living will.
b. healthcare durable power of attorney.
c. eeg.
d. survey of near-death experience

Donald is studying the eating habits of all students attending his school. he samples the population by dividing the students into groups by grade level and randomly selecting a proportionate number of students from each group. he then collects data from the sample. which type of sampling is used? select the correct answer below: systematic sampling convenience sampling stratified sampling cluster sampling