In Part I of this series, we started the process of creating user polls for a business web site. Part I gave the layout of the data layer and began the construction of the class file. In this part we will continue with adding methods to the class file that will enable the administrator to set the variable values and read from the database tables. The setPollId($iPollId) method sets the value for the _iPollId variable. Since the constructor method calls the setPollId($iPollId) method, we must...