$($a$)$

In a crash test, two midsize cars travel directly toward each other, each moving at a speed of $25\mathrm{.}0$ m$/$s$.$ They collide head$-$on and stick together. Both have a mass of $2\mathrm{.}40103$ kg$.$ The air surrounding the two cars has a temperature of $20$C$.$ What is the change in entropy $($in J$/$K$)$ of the air surrounding the two cars as a result of the collision? $($Ignore any energy carried away from the collision by sound. Assume the time it takes for the internal energy to dissipate as heat is negligible.$)$

J$/$K

$($b$)$

What If$?$ A car with the same mass and moving with the same speed as above collides head$-$on with a large van, also moving at the same speed, but with a mass of $9\mathrm{.}60103$ kg$.$ The two vehicles stick together after the collision. What is the change in entropy $($in J$/$K$)$ of the surrounding air immediately after the collision?

J$/$K

$($c$)$

For the collision in part $($b$),$ what is the change in entropy $($in J$/$K$)$ of the surrounding air from the point just after the collision to the point where the combined wreckage skids to a stop?

J$/$K