In a recent biometric study, a simple random sample of 153 adult males were poked and prodded for several hours. Among other measurements, the waist circumferences and weights of these men were recorded and the following sample statistics were recorded: 100.1 = 14.94 85.5 Sy = 17.65 = 0.8852 where x; is the waist circumference of subject j (measured in cm) and y; is the weight of subject j (measured in kg). (a) (3 pts) Use the given statistics to calculate the regression coefficients for predicting weight from waist circumference, and calculate the standard error of the estimate. Assuming that the requirements for inference on the least squares regression model are satisfied: (b) (1 pt) Find a 95% confidence interval for the population slope coefficient (8, ). (c) (1 pt) Find a 95% confidence interval for the mean weight of all adult males in the population with a waist circumference of 88 cm. (d) (1 pt) Suppose that someone claims that "adult male weight increases by more than I kg for each additional cm of waist circumference, on average". Write down the null and alternative hypotheses that you would use to test this claim, in terms of the appropriate population parameter