12.4 Higher income with experience Suppose the regression line my = -10,000 + 9500x models the relationship for the population of working adults in a country between x = experience (in years) and the mean of y = annual income

(in US dollars). The conditional distribution of y at each value of x is modeled as normal with s = 6500. Use this regression model to describe the mean and the variability around the mean for the conditional distribution at an experience of

(a) 5 years and

(b) 10 years.