What is the tree's speed of growth, in feet per year, from t = 1 yr to t = 3 yr?

A. 12 ft/yr B. 9 ft/yr The images of trees in Figure Pl.68 come from a catalog advertising fast-growing trees. If we mark the position of the top of the tree in the successive years, as shown in the graph in the figure, we obtain a motion diagram much like ones we have seen for other kinds of motion. The motion isn't steady, of course. In some months the tree grows rapidly; in other months, quite slowly. We can see, though, that the average speed of growth is fairly constant for the first few years.

Transcribed Image Text:

y (ft) 30 1-3 years 21 1 2 years 12-11 year