How to set page units and zoom in C#

using System;
using ;
using ;
using ;
using ;
using ;
using ;
namespace advanced_drawing
{
  public partial class Form2 : Form
  {
    public Form2()
    {
      InitializeComponent();
    }
    private void button1_Click(object sender, EventArgs e)
    {
      Graphics g = ();
       = ;
       = 1;
      Font rulerFont = new Font("MS Sams Serif", 8.25f);
      Pen blackPen = new Pen(, 0.05f);
      float rulerFontHeight = (g);
      RectangleF rulerRect = new RectangleF(0, 0, 6.5f, rulerFontHeight * 1.5f);
      (blackPen, , , , );
    }
  }
}