I'm a bit confused. how do transverse waves not need a medium to travel though, but cannot travel through air?

Truck traveling west on the highway experiences an acceleration to the east. what could be the cause of this acceleration

Velocity is a description of both speed and direction, therefore it - a vector - a force arrow - the same as acceleration - a magnitude

Madison pushes with a 210-n horizontal force on a 24-kg crate of coffee resting on a warehouse floor. the force of friction on the crate is 74 n. what is the acceleration?