What is the velocity in meters per second of a runner who runs exactly 110 m towards the beach in 72 seconds

Her speed is (distance/time). That's (100m/72s)= 1.528 m/s (rounded).

Her velocity is her speed and direction. That's 1.528 m/s from her starting point towards the beach.

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.