diff --git a/lectures/oo/exercicio3/atividade3.md b/lectures/oo/exercicio3/atividade3.md
index 1d729bd..d7aca51 100644
--- a/lectures/oo/exercicio3/atividade3.md
+++ b/lectures/oo/exercicio3/atividade3.md
@@ -1,4 +1,4 @@
----
+---
 title: Atividade 2 - Interfaces gráficas em Java Swing
 layout: default
 ---
@@ -31,6 +31,179 @@ O usuário deverá entrar com 3 valores, em campos de texto. O quarto valor deve
 |R$2000,00    |  R$1000,00  |0.80      |**87**    |
 
 
+REPOSTA:
+
+public class Principal {
+	
+	public static void main (String[] args) {
+		JanelaEx1 j = new JanelaEx1();
+	}
+
+}
+
+
+import javax.swing.*;
+import java.awt.*;
+
+public class JanelaEx1 extends JFrame {
+	JLabel 	lblVF,
+			lblVA,
+			lbli,
+			lbln;
+	
+	JTextField 	txtVF,
+				txtVA,
+				txti,
+				txtn;
+	
+	JButton btnCalcular,
+			btnLimpar;
+	
+	
+	public JanelaEx1() {
+		this.setTitle("Janela Principal - Exercício 1");
+		this.setSize(450,150);
+		setLayout(new GridLayout(3, 4));
+		
+		lblVF = new JLabel("VF");
+		lblVA = new JLabel("VA");
+		lbli = new JLabel("i");
+		lbln = new JLabel("n");
+		
+		txtVF = new JTextField();
+		txtVA = new JTextField();
+		txti = new JTextField();
+		txtn = new JTextField();
+		
+		btnCalcular = new JButton("Calcular");
+		btnLimpar = new JButton("Limpar");
+		
+		add(lblVF);
+		add(lblVA);
+		add(lbli);
+		add(lbln);
+		add(txtVF);
+		add(txtVA);
+		add(txti);
+		add(txtn);
+		add(btnCalcular);
+		add(btnLimpar);
+		
+		btnCalcular.addActionListener(new CalcularListener(this));
+		btnLimpar.addActionListener(new LimparListener(this));
+		
+		
+		setVisible(true);
+	}
+
+
+}
+
+
+import java.awt.event.*;
+
+public class CalcularListener implements ActionListener {
+	
+	JanelaEx1 j;
+	
+	public CalcularListener(JanelaEx1 janela) {
+		j = janela;
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent e) {
+		// TODO Auto-generated method stub
+		
+		float vf, va, i;
+		int n;
+		
+		if(j.txtVF.getText() == null || j.txtVF.getText().trim().equals("")) {
+			
+			va = Float.parseFloat(j.txtVA.getText());
+			i = Float.parseFloat(j.txti.getText());
+			n = Integer.parseInt(j.txtn.getText());
+			
+			i = (float)((i/100.0) + 1.0);
+			
+			vf = (float) (va * (Math.pow(i, n)));
+			
+			j.txtVF.setText(Float.toString(vf));
+			
+		}
+		
+		else if(j.txtVA.getText() == null || j.txtVA.getText().trim().equals("")) {
+			
+			vf = Float.parseFloat(j.txtVF.getText());
+			i = Float.parseFloat(j.txti.getText());
+			n = Integer.parseInt(j.txtn.getText());
+			
+			i = (float)((i/100.0) + 1.0);
+			
+			va = (float) (vf / (Math.pow(i, n)));
+			
+			j.txtVA.setText(Float.toString(va));
+		}
+		
+		
+		else if(j.txti.getText() == null || j.txti.getText().trim().equals("")) {
+			
+			vf = Float.parseFloat(j.txtVF.getText());
+			va = Float.parseFloat(j.txtVA.getText());
+			n = Integer.parseInt(j.txtn.getText());
+			
+			float a = (float) ((1.0) / (n));
+			float b = vf/va;
+			
+			i = (float) (((Math.pow(b, a)) - 1) * 100);
+			
+			j.txti.setText(Float.toString(i));
+			
+		}
+		
+		else if(j.txtn.getText() == null || j.txtn.getText().trim().equals("")) {
+			vf = Float.parseFloat(j.txtVF.getText());
+			va = Float.parseFloat(j.txtVA.getText());
+			i = Float.parseFloat(j.txti.getText());
+			
+			i = (float)((i/100.0) + 1.0);
+			
+			n = (int) ((Math.log10(vf/va))/(Math.log10(i)));
+			
+			j.txtn.setText(Integer.toString(n));
+		
+		}
+
+		
+	}
+
+}
+
+
+import java.awt.event.*;
+
+public class LimparListener implements ActionListener{
+	
+	JanelaEx1 j;
+	
+	public LimparListener(JanelaEx1 janela) {
+		j = janela;
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent e) {
+		// TODO Auto-generated method stub
+		
+		j.txtVF.setText(null);
+		j.txtVA.setText(null);
+		j.txti.setText(null);
+		j.txtn.setText(null);
+	
+	}
+	
+	
+
+}
+
 
 
 **Exercício 2:** Crie uma interface gráfica para cálculo dos valores obtidos ao final de cada mês para uma aplicação mensal de umdeterminado valoor e uma determinada taxa de juros. O cálculo do valor obtido ao final é dado pela seguinte fórmula: 
@@ -47,3 +220,342 @@ onde:
 
 
 Os valores finais de cada mês deverão ser informados através de objetos JLabel. 
+
+
+Respostas:
+
+
+
+
+REPOSTA 1:
+
+public class Principal {
+	
+	public static void main (String[] args) {
+		JanelaEx1 j = new JanelaEx1();
+	}
+
+}
+
+
+import javax.swing.*;
+import java.awt.*;
+
+public class JanelaEx1 extends JFrame {
+	JLabel 	lblVF,
+			lblVA,
+			lbli,
+			lbln;
+	
+	JTextField 	txtVF,
+				txtVA,
+				txti,
+				txtn;
+	
+	JButton btnCalcular,
+			btnLimpar;
+	
+	
+	public JanelaEx1() {
+		this.setTitle("Janela Principal - Exercício 1");
+		this.setSize(450,150);
+		setLayout(new GridLayout(3, 4));
+		
+		lblVF = new JLabel("VF");
+		lblVA = new JLabel("VA");
+		lbli = new JLabel("i");
+		lbln = new JLabel("n");
+		
+		txtVF = new JTextField();
+		txtVA = new JTextField();
+		txti = new JTextField();
+		txtn = new JTextField();
+		
+		btnCalcular = new JButton("Calcular");
+		btnLimpar = new JButton("Limpar");
+		
+		add(lblVF);
+		add(lblVA);
+		add(lbli);
+		add(lbln);
+		add(txtVF);
+		add(txtVA);
+		add(txti);
+		add(txtn);
+		add(btnCalcular);
+		add(btnLimpar);
+		
+		btnCalcular.addActionListener(new CalcularListener(this));
+		btnLimpar.addActionListener(new LimparListener(this));
+		
+		
+		setVisible(true);
+	}
+
+
+}
+
+
+import java.awt.event.*;
+
+public class CalcularListener implements ActionListener {
+	
+	JanelaEx1 j;
+	
+	public CalcularListener(JanelaEx1 janela) {
+		j = janela;
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent e) {
+		// TODO Auto-generated method stub
+		
+		float vf, va, i;
+		int n;
+		
+		if(j.txtVF.getText() == null || j.txtVF.getText().trim().equals("")) {
+			
+			va = Float.parseFloat(j.txtVA.getText());
+			i = Float.parseFloat(j.txti.getText());
+			n = Integer.parseInt(j.txtn.getText());
+			
+			i = (float)((i/100.0) + 1.0);
+			
+			vf = (float) (va * (Math.pow(i, n)));
+			
+			j.txtVF.setText(Float.toString(vf));
+			
+		}
+		
+		else if(j.txtVA.getText() == null || j.txtVA.getText().trim().equals("")) {
+			
+			vf = Float.parseFloat(j.txtVF.getText());
+			i = Float.parseFloat(j.txti.getText());
+			n = Integer.parseInt(j.txtn.getText());
+			
+			i = (float)((i/100.0) + 1.0);
+			
+			va = (float) (vf / (Math.pow(i, n)));
+			
+			j.txtVA.setText(Float.toString(va));
+		}
+		
+		
+		else if(j.txti.getText() == null || j.txti.getText().trim().equals("")) {
+			
+			vf = Float.parseFloat(j.txtVF.getText());
+			va = Float.parseFloat(j.txtVA.getText());
+			n = Integer.parseInt(j.txtn.getText());
+			
+			float a = (float) ((1.0) / (n));
+			float b = vf/va;
+			
+			i = (float) (((Math.pow(b, a)) - 1) * 100);
+			
+			j.txti.setText(Float.toString(i));
+			
+		}
+		
+		else if(j.txtn.getText() == null || j.txtn.getText().trim().equals("")) {
+			vf = Float.parseFloat(j.txtVF.getText());
+			va = Float.parseFloat(j.txtVA.getText());
+			i = Float.parseFloat(j.txti.getText());
+			
+			i = (float)((i/100.0) + 1.0);
+			
+			n = (int) ((Math.log10(vf/va))/(Math.log10(i)));
+			
+			j.txtn.setText(Integer.toString(n));
+		
+		}
+
+		
+	}
+
+}
+
+
+import java.awt.event.*;
+
+public class LimparListener implements ActionListener{
+	
+	JanelaEx1 j;
+	
+	public LimparListener(JanelaEx1 janela) {
+		j = janela;
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent e) {
+		// TODO Auto-generated method stub
+		
+		j.txtVF.setText(null);
+		j.txtVA.setText(null);
+		j.txti.setText(null);
+		j.txtn.setText(null);
+	
+	}
+	
+	
+
+}
+
+
+
+
+
+RESPOSTA 2:
+
+public class Principal {
+	
+	public static void main (String[] args) {
+		Janela2 j = new Janela2();
+	}
+
+}
+
+
+
+import javax.swing.*;
+import java.awt.*;
+
+public class Janela2 extends JFrame{
+	
+	JLabel 	lbldeposito,
+			lbljuros,
+			lblmeses;
+	
+	JTextField 	txtdeposito,
+				txtjuros,
+				txtmeses;
+	
+	JButton btncalcular,
+			btnlimpar;
+	
+	JLabel  [] labels = new JLabel[200];
+	
+	
+	public Janela2 () {
+		this.setTitle("Janela Principal - Exercício 2");
+		this.setSize(400,400);
+		
+		Container panel = getContentPane();
+		
+		setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
+		
+		lbldeposito = new JLabel("Deposito Mensal");
+		lbljuros = new JLabel("Taxa de Juros");
+		lblmeses = new JLabel("Tempo de Aplicação");
+		
+		txtdeposito = new JTextField();
+		txtjuros = new JTextField();
+		txtmeses = new JTextField();
+		
+		btncalcular = new JButton("Calcular");
+		btnlimpar = new JButton("Limpar");
+		
+		for (int i = 0; i < labels.length; i++) {
+			labels[i] = new JLabel();
+			add(labels[i]);
+		}
+		
+		add(lbldeposito);
+		add(txtdeposito);
+		add(lbljuros);
+		add(txtjuros);
+		add(lblmeses);
+		add(txtmeses);
+		add(btncalcular);
+		add(btnlimpar);
+		
+		btncalcular.addActionListener(new CalcularListener(this));
+		btnlimpar.addActionListener(new LimparListener(this));
+		
+		
+		setVisible(true);
+	}
+
+}
+
+
+
+
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.text.DecimalFormat;
+
+public class CalcularListener implements ActionListener {
+	
+	Janela2 j;
+
+	public CalcularListener(Janela2 janela) {
+		// TODO Auto-generated constructor stub
+		j = janela;
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent arg0) {
+		// TODO Auto-generated method stub
+		
+		float deposito = Float.parseFloat(j.txtdeposito.getText());
+		float juros = Float.parseFloat(j.txtjuros.getText());
+		int meses = Integer.parseInt(j.txtmeses.getText());
+		
+		
+		
+		float jurosn;
+		float jurosmais;
+		float resultado;
+		String escreve;
+		
+		jurosn = (float) (juros/100);
+		jurosmais = (float)((juros/100) + 1.0);
+		
+		
+		for (int i = 0; i < meses; i++) {
+			
+			resultado = (float) (jurosmais * (((Math.pow(jurosmais, i + 1)) - 1)/jurosn) * deposito);
+			
+			DecimalFormat df = new DecimalFormat("0.00");
+			
+			escreve = "\nMês " + (i + 1) + ": " + df.format(resultado);
+			
+			j.labels[i].setText(escreve);
+		}
+
+
+	}
+
+}
+
+
+
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+public class LimparListener implements ActionListener {
+	
+	Janela2 j;
+
+	public LimparListener(Janela2 janela) {
+		// TODO Auto-generated constructor stub
+		j = janela;
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent arg0) {
+		// TODO Auto-generated method stub
+		
+		j.txtdeposito.setText(null);
+		j.txtjuros.setText(null);
+		j.txtmeses.setText(null);
+		
+		for(int i = 0; i < 200; i++) {
+			j.labels[i].setText(null);
+		}
+
+	}
+
+}
+
+