DUE IN TWO HOURS

ASAP PLEASE!!!

Given the following specification, design a class diagram using PlantUML. To design the class diagram, use abstract (10 points), static (10 points), package (20 points ), namespace (20 points ), association (20 points ), and generalization (20 points ) on PlantUML

Specification:

• A school has a principal, many students, and many teachers. Each of these persons has a name, birthdate, and may borrow and return books. The book class must contain a title, abstract, and when it is available. Teachers and the principal are both paid a salary.
• A school has many playgrounds and rooms. A playground has many swings. Each room has many chairs and doors. Rooms include offices, restrooms, classrooms, and a cafeteria. Each classroom has many computers and desks. Each desk has many rulers.  

Submit a DOC/PDF file including PlantUML script and diagram.

Hello I'm currently having an error that says "main is not abstract and does not override abstract method" is there a way to fix the error?

import java.io.IOException;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.stage.Stage;
import static javafx.application.Application.launch;
import javafx.scene.layout.StackPane;
public class Main extends Application implements EventHandler<ActionEvent>{
    public static void main(String[] args){
        launch(args);
    }
    @Override
    public void Start(Stage stage){
        stage.setTitle("Test");
        Button calcButton = new Button("Steam");
      
        StackPane root = new StackPane();
        calcButton.setOnAction(this);
      
        Scene scene = new Scene(root, 100, 100);
      
        stage.setScene(scene);
        stage.setTitle("Test");      
        stage.show();

    }
    class CalcButtonHandle {
      
        public void handle(ActionEvent event) throws IOException
        {
        Main fo = new Main();
        fo.runOt("D:\\Steam\\Steam.exe");
        }
    }
  
    public void runOt(String path) throws IOException{
        Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler " + path);
    }
}
  

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