Q1]

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class BlinkingText implements Runnable {
    private JLabel label;

    public BlinkingText() {
        JFrame frame = new JFrame("Blinking Text");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 200);
        
        label = new JLabel("Blinking Text");
        label.setFont(new Font("Arial", Font.BOLD, 20));
        frame.add(label, BorderLayout.CENTER);

        frame.setVisible(true);
    }

    @Override
    public void run() {
        try {
            while (true) {
                Thread.sleep(500); 
                label.setVisible(!label.isVisible());
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        BlinkingText blinkingText = new BlinkingText();
        Thread thread = new Thread(blinkingText);
        thread.start();
    }
}

Q2]

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.*;
class Slip16_2 extends JFrame implements ActionListener
{ 
 JTextField t1,t2,t3;
 JButton b1,b2,b3;
 JTextArea t;
 JPanel p1,p2;
 Hashtable ts;
 Slip16_2()
 {
 ts=new Hashtable();
 t1=new JTextField(10);
 t2=new JTextField(10);
 t3=new JTextField(10);
 b1=new JButton("Add");
 b2=new JButton("Search");
 b3=new JButton("Remove");
 t=new JTextArea(20,20);
 p1=new JPanel();
 p1.add(t);
 p2= new JPanel();
 p2.setLayout(new GridLayout(2,3));
 p2.add(t1);
 p2.add(t2);
 p2.add(b1);
 p2.add(t3);
 p2.add(b2);
 p2.add(b3);
 add(p1);
 add(p2);
 b1.addActionListener(this);
 b2.addActionListener(this);
 b3.addActionListener(this);
 setLayout(new FlowLayout());
 setSize(500,500);
 setVisible(true);
 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 }
 public void actionPerformed(ActionEvent e)
 {
 if(b1==e.getSource())
 {
 String name = t1.getText();
 int code = Integer.parseInt(t2.getText());
 ts.put(name,code);
 Enumeration k=ts.keys();
 Enumeration v=ts.elements();
 String msg="";
 while(k.hasMoreElements())
 {
 msg=msg+k.nextElement()+" = "+v.nextElement()+"\n";
 }
 t.setText(msg);
 t1.setText("");
 t2.setText("");
 }
 else if(b2==e.getSource())
 {
 String name = t3.getText();
 if(ts.containsKey(name))
 {
 t.setText(ts.get(name).toString());
 }
 else
 JOptionPane.showMessageDialog(null,"City not found ...");
 }
 else if(b3==e.getSource())
 {
 String name = t3.getText();
 if(ts.containsKey(name))
 {
 ts.remove(name);
JOptionPane.showMessageDialog(null,"City Deleted ...");
 }
 else
 JOptionPane.showMessageDialog(null,"City not found ...");
 }
 }
 public static void main(String a[])
 {
 new Slip16_2();
 }
}