a truck on the freeway, traveling at 30 m/s slams on the brakes. the truck comes to a rest in 4.7 seconds & travels 70 meters while stopping. what was the trucks acceleration while braking?

With i really need the correct answer!

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.

In addition to gravity, what is the other predominant force that affects the motion of a pendulum?