C# Language:

Design a class called shop from the following Abstract class (inherit iShop class) iShop. The shop class must keep a list of items or array of items. A shop object can sell, return and purchase item.

public abstract class iShop

{

abstract public bool sellItem(String itemName, int quantity);

abstract public bool returnItem(String itemName, int quantity);

abstract public bool purchaseItem(String itemName, int quantity);

}

Demonstrate the shop class within the Main method.