The value of (a-1)+a^2-b^2/1-ab+2(a-b)/2b when a=2 and b=-1 is ?

an advantage of the standard deviation is that it increases as the dispersion of the data increases. e. 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.

4th option is correct xy=-10

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