The nearest lot line of the lot or parcel of land to be used as a public garage or gasoline service station shall be at least three hundred (300') feet, measured in a straight line, from the nearest lot line of any lot upon which is located any building used as a theater, auditorium, or other place of public assembly, capable of seating over 100 persons, or used as a church, hospital for humans, college, school, public library, or institution for dependents or children, or any public playground or athletic field.