The classification is based on the definitions provided in the 'Introduction' section of the context. Scalar quantities are defined as those involving only magnitude (one value), such as time, distance, and work. Vector quantities involve both magnitude and direction, such as force and velocity. The text explicitly lists 'time' and 'distance' under scalars, and 'force' and 'velocity' under vectors. 'Work' is also explicitly listed as a scalar quantity.