Chapter 27, Problem 27.38E

a.

To determine

To plot: The means for each of the three treatments against year, connecting the yearly means for each treatment by lines to show the pattern over time and use the same plot for all three treatments with a different color for each treatment.

(b)

To determine

To check: Whether more water in the wet season increases plant growth and also gives the conclusion about dry season.

To identify: Which addition of water has the larger effect?

(c)

To determine

To identify: In which three years the treatment means differ significantly.

(d)

To determine

To describe: The effect of the natural rainfall show up in obtained plot when there were unusual late rains during the spring in 2005.