private void stdnt_result_back_btn_Click(object sender, EventArgs e)
 {
     Student st = new Student();
     st.Show();
     this.Hide();
 }
 private void stdnt_pay_btn_Click(object sender, EventArgs e)
 {
     Student student = new Student();
     student.Show();
     this.Hide();
 }
 private void show_info_back_btn_Click(object sender, EventArgs e)
 {
     Student student = new Student();
     student.Show();
     this.Hide();
 }