Choose the correct forms of salutation in the business letter（）
A. Dear Mr. Smith
B. Dear John
C. Dear Sir/Madam
Dear Gentlemen
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A key difference between calculating the sample mean and the population mean is（）
A. we use and n instead of μ and N
B. we divide the sum of the observations by n – 1 instead of n
C. the sample observations are ranked and the middle value is selected as the population mean
D. there are no differences
We would make you the following offer, subject to your telex acceptance us not later than June 30, 1998（）
A. reaches
B. being reached
C. reaching
D. reach
For a data set, the coefficient of skewness is -2.73. We conclude that（）
A. the mean is larger than the median
B. the median is larger than the mean
C. the standard deviation is a less than zero
D. something is wrong because the coefficient of skewness cannot be less than -1
Which measure of central tendency reports the value that occurs with the highest frequency（）
A. Mean
B. Median
C. Mode
D. Standard deviation
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