Write the Word or Phrase That Best Completes Each Statement

Write the word or phrase that best completes each statement or answers the question.
-In a study of feeding behavior, zoologists recorded the number of grunts of a warthog feeding by a lake in the 15 minute period following the addition of food. The data showing the weekly number of grunts and the age of the warthog (in days) are listed below:
$\begin{array}{ccl}\hline \text { Week } & \text { Number of Grunts } & \text { Age (days) } \\\hline 1 & 81 & 116 \\2 & 59 & 132 \\3 & 30 & 146 \\4 & 35 & 151 \\5 & 54 & 158 \\6 & 31 & 165 \\7 & 53 & 174 \\8 & 8 & 180 \\9 & 11 & 186 \\\hline\end{array}$

a. Write the equation of a straight-line model relating number of grunts (y) to age $( \mathrm { x } )$ .
b. Give the least squares prediction equation.
c. Give a practical interpretation of the value of $\hat { \beta } _ { 0 }$ if possible.
d. Give a practical interpretation of the value of $\hat { \beta } _ { 1 }$ if possible.