Harbor View Mooring wants to modify the demonstration program to more closely match their actual setup. Although most of their mooring slips are uncovered, opened to the weather elements, others are covered. Some of the covered slips also have a door to further protect the boat from being affected by adverse weather conditions. In demonstrating the ability of an object-oriented class to inherit the properties of its base class, and thus cut down on development time, you need to extend the Slip Class to create a Covered Slip Class. The covered slip will include all the information of the regular slip, but will also have a height. Because some of these covered slips also have doors (and others do not), you need to track this information for each covered slip.