Speed is a scalar quantity that refers on how fast and object is moving, speed can be thought of as the rate at which and object covers distance. An object with no movement at all has a zero speed.
Cant be velocity because it has to include distance for example "80 miles toward east"
acceleration is almost as velocity just includes going faster or slower or turning.
All of them. Air because in helps make food it also lets the plant breath. Water because it helps move nutrients into the plant. Soil because plants can’t grow without soil.
