var imgArr = new Array(3);
imgArr[0]= "assets/images/Math_popup_pg1.jpg";
imgArr[1] = "assets/images/Math_popup_pg2.jpg";
imgArr[2]= "assets/images/Math_popup_pg3.jpg";
imgArr[3]= "assets/images/Math_popup_pg3.jpg";
imgArr[4]= "assets/images/Math_popup_pg3.jpg";
imgArr[5]= "assets/images/Math_popup_pg3.jpg";
imgArr[6]= "assets/images/Math_popup_pg3.jpg";
imgArr[7]= "assets/images/Math_popup_pg3.jpg";
imgArr[8]= "assets/images/Math_popup_pg3.jpg";

function ShowImagePanel()
{
    var image_panel = document.getElementById('image_panel');
    
    w = 722;
    h = 1350;

    xc = Math.round((document.body.clientWidth/2)-(w/2))
    yc = Math.round((document.body.clientHeight/2)-(h/2))
    
    image_panel.style.left = xc + "px";
    image_panel.style.top  = yc + "px";
    image_panel.style.display = 'block';
}

function ShowImagePanel1()
{
    var image_panel1 = document.getElementById('image_panel1');
    
    w = 722;
    h = 1350;

    xc = Math.round((document.body.clientWidth/2)-(w/2))
    yc = Math.round((document.body.clientHeight/2)-(h/2))
    
    image_panel1.style.left = xc + "px";
    image_panel1.style.top  = yc + "px";
    image_panel1.style.display = 'block';
}

function ShowImagePanel2()
{
    var image_panel2 = document.getElementById('image_panel2');
    
    w = 722;
    h = 1350;

    xc = Math.round((document.body.clientWidth/2)-(w/2))
    yc = Math.round((document.body.clientHeight/2)-(h/2))
    
    image_panel2.style.left = xc + "px";
    image_panel2.style.top  = yc + "px";
    image_panel2.style.display = 'block';
}