Fertilizer needs to be applied during the fastest growth of the plant. Below is the graph of the growth cycle of a flowering shrub.

1. Using complete sentences, write a detailed statement describing the growth of this shrub for $0 ≤ t ≤ 5$ months.

   Hint (a):

   Pay attention to variance in the slope of the graph.

2. During which time $t$ should the plant be fertilized?

   Hint (b):

   When does the fastest growth of the plant occur?

3. Approximately how fast is the shrub growing at $t = 3$? How did you get your answer?

   Steps (c):

   Estimate the slope of the secant line at $t = 3$.

   Answer (c):

   $\approx \frac{3}{4}\text{ feet/month}$

4. What is the shrub's average rate of growth over the complete growth cycle? How did you get your answer?

   Hint (d):

   The average rate of growth is the slope of the secant line between $t = 0$ and $t = 5$.