Answer 1

Partial Functions are those Functions Which are not fully Defined within the Body of that Function, i.e., Some part of Code is written Somewhere else but must be execute along with this function in order to get the full result.
let me quote an example, if u want develop a WPF(Windows Presentation Foundation) App with C Sharp Than the main Function is Partial Because The User Interface is Defined Somewhere Else i.e, in XAML file Which must be Executed Along with Main Function In Order to Run the Application. XAML Displays The UI(user interface) And partial main function does the actually Work Behind the scene.
Hope U Got The Right Answer.