3. In the formula for calculating the variance, what does the letter “n” represent?
A. Sample size
B. Population size
C. Lowest score
D. Highest score
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2. Which measure of variability is most general, and hence least useful?
A. Variance
B. Standard deviation
C. Mode
D. Range
4. What do the majority of the people in the world use for health care?
A. Strange and wonderful equipment.
B. Factory-produced chemicals.
C. Modern medicines.
D. Plants.
3. It is believed by scientists that traditional medicines__________.
A. can cure all kinds of diseases.
B. may cure some of today's most serious diseases
C. are no longer useful for modem men.
D. are too cheap to be useful.
2. Which of the following statements is NOT true?
A. Modern medicines are now available all over the world.
B. Many big and modem hospitals are expensive.
C. Traditional medicines are neither mysterious nor magical.
D. Humans have used some kinds of medicines since earliest days.
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