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(a) Describe the relationship between height and weight

It is a positive relationship, it is linear. There are a few outliers but it does not seems critical.

(b) Write the equation of the regression line. Interpret the slope and intercept in context.

Weight_hat = -105.0113 + 1.0176 x height.

Slope: For each additional centimeter in height,the model predicts the average weight to be 1.0176 additional kilograms.
Intercept: when it is 0 centimeters tall, the weight will be -105.0113 kilograms. This is obviously not possible.

(c) Do the data provide strong evidence that an increase in height is associated with an increase in weight? State the null and alternative hypotheses, report the p-value, and state your conclusion.

Ho: the true slope coefficient of height is 0
Ha: the true slope coefficient of height is greater than 0

(d) The correlation coecient for height and weight is 0.72. Calculate R2 and interpret it in context.

R-square = 0.72*0.72=0.52.