[mm] A pediatrician wishes to study how the average weight Y (in kilograms} of children changes during the rst year of life. He plots these averages versus the age I (in months) and decides to fit a least-squares regression line to the data with X as the explanatory variable and Y as the response variable. He computes the following quanties: [0W] [ppp] r = correlation between X and Y = 0.34 [:1qu _ = mean of the values of X = 5.69 x [m] _ = mean of the values of Y = 6.26 Y [sss] = standard deviation of the values of X = 3.23 s x (tn) = standard deviation of the values of Y = 2.04 5y