The difference between the sample mean and the population mean is called the: A: population deviation. B: population standard deviation. C: standard error of the mean. D: sampling error.

Which of the following statements about the arithmetic mean is not always correct? A: The mean is a measure of the middle (centre) of a distribution. B: Half of the observations are on either side of the mean. C: The sum of the deviations from the mean is zero. D: The value of the mean times the number of observations equals the sum of all of the observations.

What does the word "pedestrian" in Line 2, Para. 5 possibly mean A: Secretive. B: Illegal. C: Ordinary. D: Dishonest and mean.

Which of the following statement is not included in the characteristics of direct communication style？（ ） A: Yes may mean maybe or even no. B: Speakers often say what they mean. C: Speakers often mean exactly what they say. D: There is no need to read between the lines.

2.Which of the following about the normal distribution is NOT true A: Theoretically, the mean, median, and mode are the same. B: About 2/3 of the observations fall within ±1 standard deviation from the mean. C: It is a discrete probability distribution. D: Its parameters are the mean, μ, and standard deviation, σ.

Which of the following statement concerning about the arithmetic mean is FALSE（） A: It is less than or equal to the geometric mean. B: It is a commonly used measure of central tendency. C: It is equal to the median and mode in symmetric distributions.

Which of the following is not the way we ask for explanation or clarification? A: What do you mean by …? B: I am sorry. I don’t understand what … means. C: I am sorry, I am not sure I understand what you mean. Do you mean…? D: Repeat, please.

I don’t _______ what you mean.

Explain and illustrate what “compromising” and “the spread of English” mean.

S______ synonyms are the synonyms that differ slightly in what they mean.