private void button16_Click(object sender, EventArgs e)
        {
            SimpleCalculationUI simple = new SimpleCalculationUI();

            simple.ShowDialog();
        }
 private void button13_Click_1(object sender, EventArgs e)
 {
     SimpleCalculationUI calculation = new SimpleCalculationUI();
     calculation.ShowDialog();
 }
        private void button13_Click(object sender, EventArgs e)
        {
            SimpleCalculationUI calculation = new SimpleCalculationUI();

            calculation.ShowDialog();
        }
 private void button16_Click(object sender, EventArgs e)
 {
     SimpleCalculationUI simple=new SimpleCalculationUI();
     simple.ShowDialog();
 }