A $28,467-$lb truck enters an emergency exit ramp at a speed of $\backslash (\backslash$mathbf$\{78.3\}\backslash$mathrm$\{$ft$\}/\backslash$mathrm$\{$s$\}\backslash ).$ It travels for $\backslash (\backslash$mathbf$\{4.9\}\backslash$mathrm$\{$s$\}\backslash )$ before its speed is reduced to $\backslash (\backslash$mathbf$\{41.5\}\backslash$mathrm$\{$ft$\}/\backslash$mathrm$\{$s$\}\backslash ).$ Determine the braking force by the truck if the acceleration is constant. $($Use Impulse$-$Momentum concepts.$)$

Assume theta $\backslash (=21\mathrm{.}4\backslash )$ degrees

Calculate your answer to two decimal places.

Question $2$

What are the appropriate units for the answer to Question $1?$

$-$ lb