James R. answered 06/28/19
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In a typical X-Y graph, the Range represents the set of possible output (Y) values of the graph. Since it is given that the Y axis represents the number of users, in thousands, the Range thus represents the number of users for various values of the input (Domain), which in this case is the "Number of Months."
Hence, the correct answer is A. You would expect that, in the beginning of the first month (x=0) the total number of users would be 0 (zero), and grow to some number by the end of the first month (x = 1), followed sequentially by the number of users at the end of each subsequent month, up through the end of month 12 (x=12).
The rate of growth of users from month to month can then be determined computing the slope of the line connecting those two months, or a regression analysis could be done to determine a best-fit for a line spanning 2 or more months.
The last sentence in the problem statement is ambiguous. They appear to be values of Y (the value X=12.5 does not exist), but we do not know for which values of X they were measured, so the information is extraneous and has no bearing on the answer to the question.