how do you determine which class is extended from which class?

Application hierarchy browser tool

Which tool shows where the relation between two tables is defined?

Microsoft Visio.

Which tool is appropriate to find out where the label on an Extended Data Type is defined?

The Application Hierarchy Browser, where the information can

be read in the right detail section of the form, when the extended

data type is selected

What is the use of help system?

help system gives the documents ,if you need help with  application

How do you compare the two application objects?

using compare tool

What is use of Find Tool?

This tool is used to locate the certain method or a certain line of code. Some times  Developers needs to see previously developed source code(methods). To find that source quickly this tool is useful.

For example ,you want write execute query()method in a form. If you are facing any problem in developing that  method, you need to identify the similar methods in the application. Then move the cursor to forms node, then ctr+f,enter the method name ,press ok. Then you will get all the executequery() methods existed in forms.