No person while upon a bicycle, skateboard, roller skates, or riding in or by means of any coaster, toy vehicle or similar device shall conduct himself in such a manner as to be a nuisance, safety hazard or endangerment to himself, pedestrians, other forms of traffic, the operation of businesses or to the quiet enjoyment of the residents of the city.
(b)
no person shall ride, use or operate any bicycle, skateboard, rollers skates, coaster, toy vehicle or similar device upon a sidewalk in the commercial areas of the city. the commercial areas are defined as plant street, east from highland avenue to dillard street, and south dillard street to highway 50, or any other areas of the city, such as shopping centers, of any size, where the predominance of buildings or structures in the area are commercial or business in nature.

i am making an assignment in civics, but i do not know what this means. : )