draw string in in parts of a custom pie chart in C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication5
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        int i1;
        int i2;
        int i3;
        int i4;
       
        float total;
        float deg1 ;
        float deg2 ;
        float deg3 ;
        float deg4;
        
        private void Form1_Load(object sender, EventArgs e)
        {
        
        }

        private void button1_Click(object sender, EventArgs e)
        {

            i1 = int.Parse(textBox1.Text);
            i2 = int.Parse(textBox2.Text);
            i3 = int.Parse(textBox3.Text);
            i4 = int.Parse(textBox4.Text);


            total = i1 + i2 + i3 + i4;
            deg1 = (i1 / total) * 360;
            deg2 = (i2 / total) * 360;
            deg3 = (i3 / total) * 360;
            deg4 = (i4 / total) * 360;


            Pen p = new Pen(Color.Black, 2);

            Graphics g = this.CreateGraphics();
          
            Rectangle rec = new Rectangle(textBox1.Location.X + textBox1.Size.Width + 10, 12, 150, 150);


            Brush b1 = new SolidBrush(Color.Red);
            Brush b2 = new SolidBrush(Color.Blue);
            Brush b3 = new SolidBrush(Color.Black);
            Brush b4 = new SolidBrush(Color.BlueViolet);

            SolidBrush BlackBrush = new SolidBrush(Color.Black);

            g.Clear(Form1.DefaultBackColor);
            g.DrawPie(p, rec, 0, deg1);
            g.FillPie(b1, rec, 0, deg1);
            


            g.DrawPie(p, rec, deg1, deg2);
            g.FillPie(b2, rec, deg1, deg2);
            g.DrawPie(p, rec, deg2 + deg1, deg3);
            g.FillPie(b3, rec, deg2 + deg1, deg3);
            g.DrawPie(p, rec, deg3 + deg2 + deg1, deg4);
            g.FillPie(b4, rec, deg3 + deg2 + deg1, deg4);

        }

    }
}