Chapter 4.4, Problem 13E

Special Rounding Instructions For this exercise set, round all regression parameters to three decimal places but round all other answers to two decimal places unless otherwise indicated.

Grazing Rabbits The amount $A$ of vegetation (measured in pounds) eaten in a day by a grazing animal is a function of the amount $V$ of food available (measured in pounds per acre). Even if vegetation is abundant, there is a limit, called the satiation level, to the amount the animal will eat. The following table shows, for rabbits, the difference $D$ between the satiation level and the amount $A$ of food eaten for a variety of values of $V$.

$V=vegetaionlevel$	$D=satiationlevel-A$
27	0.16
36	0.12
89	0.07
134	0.05
245	0.01

a. Draw a plot of $D$ versus $V$.

b. Find an exponential function that approximates $D$.

c. The satiation level of a rabbit is 0.18 pound per day. Use this, together with your work in part b, to find a formula for $A$.

d. Find the vegetation level $V$ for which the amount of food eaten by the rabbit will be 90% of its satiation level of 0.18 pound per day.