private void button4_Click(object sender, EventArgs e)
        {
            Xe_Bus3 lv3 = new Xe_Bus3();

            lv3.Show();
            this.Close();
        }
        private void Next_Click(object sender, EventArgs e)
        {
            Xe_Bus3 xebus = new Xe_Bus3();

            xebus.Show();
            this.Close();
        }