Discuss which random sampling techniques are adopted in the following studies. a. A researcher wants to find out the prevalence of anemia in school students. He splits schools into rural, urban, and peri-urban as the prevalence may be quite distinct between these regions. The second step 1 is to take a simple random sample within each categorized area in proportion to the numbers enrolled in the schools in each area.
b. There are 24 canopy trees in the sampling universe of interest, and you want to take 10 measurements from a subset of this group. You number each tree (1-24), put numbers in a hat, and pick ten at random. The tree corresponding to the number is now part of your sampling subset.
c. From the Yellowpage book of the current year, you pick out 20 pet stores at random.
d. A researcher wants to examine the growth patterns of a specific plant growing national wide in U. S.A. Out of 50 states, he selected 10 states at random. Within the selected states, he picks out 15 cities at random in each state. Then He collects the plants from the chosen cities.

Name and describe the three most important measures of central tendency. choose the correct answer below. a. the mean, sample size, and mode are the most important measures of central tendency. the mean of a data set is the sum of the observations divided by the middle value in its ordered list. the sample size of a data set is the number of observations. the mode of a data set is its highest value in its ordered list. b. the sample size, median, and mode are the most important measures of central tendency. the sample size of a data set is the difference between the highest value and lowest value in its ordered list. the median of a data set is its most frequently occurring value. the mode of a data set is sum of the observations divided by the number of observations. c. the mean, median, and mode are the most important measures of central tendency. the mean of a data set is the product of the observations divided by the number of observations. the median of a data set is the lowest value in its ordered list. the mode of a data set is its least frequently occurring value. d. the mean, median, and mode are the most important measures of central tendency. the mean of a data set is its arithmetic average. the median of a data set is the middle value in its ordered list. the mode of a data set is its most frequently occurring value.