Write the Word or Phrase That Best Completes Each Statement $0 \mathrm { mph }$

Write the word or phrase that best completes each statement or answers the question.
-In a comprehensive road test on all new car models, one variable measured is the time it takes a car to accelerate from 0 to 60 miles per hour. To model acceleration time, a regression analysis is conducted on a random sample of 129 new cars.
TIME60: y = Elapsed time (in seconds) from $0 \mathrm { mph }$ to $60 \mathrm { mph }$
MAX: $x _ { 1 } =$ Maximum speed attained (miles per hour)
Initially, the simple linear model $\mathrm { E } ( \mathrm { y } ) = \beta _ { 0 } + \beta _ { 1 } \mathrm { x } _ { 1 }$ was fit to the data. Computer printouts for the analysis are given below:
UNWEIGHTED LEAST SQUARES LINEAR REGRESSION OF TIME60


$\begin{array}{llll}\text { R-SQUARED } & 0.6960 & \text { RESID. MEAN SQUARE (MSE) } & 1.28695 \\\text { ADJUSTED R-SQUARED } & 0.6937 & \text { STANDARD DEVIATION } & 1.13444\end{array}$



CASES INCLUDED 129 MISSING CASES 0
Find and interpret the estimate $b _ { 1 }$ in the printout above.