A: Find the number of ways of putting 5 letters in the envelope in such a way that no letter is being put in the right envelope. B. In a holiday party, each 6 attendants brings in a gift and exchanges it with someone

else in the party. Find the number of ways of exchanging so that no one gets his/her gift back.

C. If you have 7 pairs of parentheses then how many valid groups of them one can make?

D. The number of ways one can triangulate a regular polygon with 5 sides is…?

Explain the circumstances for which the interquartile range is the preferred measure of dispersion. what is an advantage that the standard deviation has over the interquartile range? choose the correct answer below. a. the interquartile range is preferred when the distribution is symmetric. an advantage of the standard deviation is that it increases as the dispersion of the data increases. b. the interquartile range is preferred when the data are not skewed or no have outliers. an advantage of the standard deviation is that it uses all the observations in its computation. c. the interquartile range is preferred when the distribution is symmetric. an advantage of the standard deviation is that it is resistant to extreme values. d. the interquartile range is preferred when the data are bell shaped. an advantage of the standard deviation is that it is resistant to extreme values. e. the interquartile range is preferred when the data are skewed or have outliers. an advantage of the standard deviation is that it uses all the observations in its computation. f. the interquartile range is preferred when the data are bell shaped. an advantage of the standard deviation is that it increases as the dispersion of the data increases.