if (!document.getElementById){
alert("Your browser may not support certain required Javascript features used on this page. If you experience trouble, please send us an email at olcsupport@mcgrawhill.ca, including the name and version of your browser and your computer's operating system (eg WinXP, MacOS X, etc.)");
}


var currentSlide = 0;

var answerBut = "<p><form><input type=\"button\" value=\"Display the answer\" onclick=\"displayFeedback();\" /></form></p>";

// -------------------------------------
function displayExhibit(which) {

if (currentSlide == 0) {
	var navButtons = document.getElementById('navDiv');
	var navButs = "<input type=\"button\" value=\"Previous Exhibit\" onclick=\"displayExhibit(-1);\" /><input type=\"button\" value=\"Next Exhibit\" onclick=\"displayExhibit(1);\" />";
	navButtons.innerHTML = navButs;
}

var etitle = document.getElementById('titleDiv');
var image = document.getElementById('imgDiv');
var button = document.getElementById('buttonDiv');

var ans = document.getElementById('feedbackDiv');
ans.innerHTML = '';

if (which > 0) {
	currentSlide = currentSlide + 1;
	if (currentSlide > slideCount) {
		currentSlide = 1;
	}
} else {
	currentSlide = currentSlide - 1;
	if (currentSlide < 1) {
		currentSlide = slideCount;
	}
}

etitle.innerHTML = "<p style=\"margin-bottom: 0px; font-family: verdana,arial,helvetica; font-size: 8pt;\">Exhibit " + currentSlide + "</p><h4 style=\"margin-top: 5px;\">" + titles[currentSlide] + "</h4>";

image.innerHTML = "<p><img src=\"http://www.mcgrawhill.ca/college/olcsupport/mcshane6e/eSG/understanding_images/mcshane_" + chapter + "_" + currentSlide + ".jpg\" /></p>";

button.innerHTML = "<p><form><input type=\"button\" value=\"Display the answer\" onclick=\"displayFeedback();\" /></form></p>";

}

// -------------------------------------
function displayFeedback() {
var ans = document.getElementById('feedbackDiv');
ans.innerHTML = feedbacks[currentSlide];
}