The 2 answers are: A and D
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Explanations
A. True. This is because there are 13 dots shown. You cannot use the box plot to determine this.
B. False. This contradicts choice A above. Also, we cannot use the box plot to determine how many people there are. What 12-7 = 5 is showing is that the range is 5. This means the range for the age of runners is 5 years. In other words, 5 years is the span from the youngest (age 7) to the oldest (age 12).
C. False. The median is 10 as its shown in the box plot. Recall the median for any box and whisker plot is the vertical line inside the box.
D. True. The vertical line inside the box is the median. This vertical line does not have to be exactly halfway between the left and right edges of the box.
E. False. A box plot can be used to determine variability (in terms of range and IQR). You can determine the variability from a dot plot, though you'll have to do a bit of work to get it.
F. False. Refer to choice E.