Suppose we have the following data The summary statistics ar

Suppose we have the following data: The summary statistics are summation x_i = 24.0, summation y_i = 312.5, summation x_i^2 = 70.5, summation y_i^2 = 11626.75, beta_0 = 6.4487818, beta_1 = 10.602564. Does the simple linear regression specify a useful relationship between x and y? Estimate the change in y with one increase in x, using a 95% confidence interval. Calculate a 95% Cl for mu_y when the x* = 3.0. Calculate a 95% PI for a future Y observation when x* = 3.0. Would the 95% Cl and PI when x* = 2.5 be wider or narrower than the corresponding results in (c) and (d)? Answer without actually computing the interval. Would you recommend calculating a 95% PI for x* = 6.0? Explain.

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