Explain the relationship between velocity and acceleration. are these scalar or vector quantities?

According to newton's second law: F=MA

Or, force equals mass times acceleration.

Scalar quantities are measurements WITHOUT a direction. Example, speed. Speed measures how fast you are going, but not what direction you are going. Therefore mass is considered a scalar since you can measure how much mass an object has, but since the mass doesn't have to be moving it does not have an associated direction.

Conversely, velocity is a vector. Vectors are measurements WITH a direction. Velocity by definition is speed in a direction therefore by definition it is a vector. Acceleration is defined as change in velocity over a change in time and therefore is also a vector.