Look once more at the data from the Tour de France. In Exercise 46, we looked at the whole history of the race, but now let's consider just the post-World War II era.
a) Find the regression of Avg Speed by Year only for years from 1947 to the present. Are the conditions for regression met?
b) Interpret the slope.
c) In 1981, Bernard Hainault averaged 39.86 kph, while in 2013, Christopher Froome averaged 40.55 kph. Which was the more impressive performance? Why?