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Use the dataset attached on blackboard and answer the following questions:

a) First study the simple linear regression model for the heart attack death rates, on the only basis of the number of phones. Determine whether the number of phone is associated significantly with the heart attack death rate.

b) Write the multiple linear regression model for the heart attack death rates on the basis of the number of phones and the proportion of saturated fat. Compute the associated least squares coefficient estimates.

c) Test whether at least one of the predictors number of phones, or proportion of saturated fat, is useful in predicting the heart attack death rate.

d)  Compute the R2 statistic, and the residual standard error for the models in questions (b) and (c). Would you say that adding the proportion of saturated fat to the model significantly improves the accuracy?

e)  Write the multiple linear regression model for the heart attack rates on the basis of the number of phones, the proportion of saturated fat, and the proportion of animal fat. Compute the associated least squares coefficient.

f)  A country has the following features: 108 phones per 1000 inhabitants; 33% of saturated fat for men between the ages of 55 and 59; 7% of animal fat for men between the ages of 55 and 59.

Predict the heart attack death rate for men between the ages of 55 and 59 in that country.

g)  Which coefficient estimates are significantly non-zero?