Mountainside communities often have plans in place to keep people safe during a natural disaster. Place the mass movements in order based on the amount of reaction time the community members will have to get to safety. Start with the mass movement event that gives people the least amount of time to react.

Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point