function com_assoc_mult_check()

{

	var str = document.forms[0].elements[0].value;

	if( str == 810 )

	{

		alert("Correct!");

	}

	else

	{

		alert("No, that's not quite right.");

	}

	return false;

}



function robots_check()

{

	if( parseInt(document.forms[0].elements[0].value) == 30000 )

	{

		self.parent.top.location="robots2.html";

	}

	else

	{

		alert("That value won't align the tubes.");

	}

	return false;

}



function ordofops_check()

{

	if( parseInt(document.forms[0].elements[0].value) == 920 )

	{

		alert("Correct! Click on \'Next'\ (down below) to go on.");

	}

	else

	{

		alert("No, that isn't correct.");

	}

	return false;

}



function ordofops_2_check()

{

	if( CheckAllAnswers() )

	{

		alert("Correct!");

	}

	else

	{

		alert("No, you seem to have an error in one of the calculations.");

	}

	return false;

}



function CheckAllAnswers()

{

	var dfe=document.forms[0].elements;

	return ( parseInt(dfe[0].value) == 8 && parseInt(dfe[1].value) == 3 && parseInt(dfe[2].value) == 2 && parseInt(dfe[3].value) == 8 && parseInt(dfe[4].value) == 8 && (parseFloat(dfe[5].value) == 0.5 || dfe[5].value == "1/2") && parseInt(dfe[6].value) == 5); 

}



function robot_arm_check()

{

	var dfe=document.forms[0].elements;

	if ( dfe[0].options[0].selected && dfe[1].options[1].selected && dfe[2].options[2].selected && dfe[3].options[1].selected && dfe[4].options[3].selected )

	{

		alert("That is correct!");

	}

	else

	{

		alert("No, that is not correct.");

	}

	return false;

}	



function distrib_check()

{

	var str = document.forms[0].elements[0].value;

	if( str.indexOf("francs") != -1 )

	{

		str = str.substr(0, str.indexOf("francs") );

	}

	if( parseInt(document.forms[0].elements[0].value) == 450 )

	{

		alert("Correct!");

	}

	else

	{

		alert("Nope, that isn't right.");

	}

	return false;

}



function zeroprop_check()

{

	var str = "";

	for(var i = 0; i < document.forms[0].elements[0].value.length; i ++ )

	{

		if( document.forms[0].elements[0].value[i] != " " )

		{

			str += document.forms[0].elements[0].value[i];

		}

	}

	document.forms[0].elements[0].value = str;

	if( str == "50-50=0" || str == "50+-50=0" || str == "50+(-50)=0" || str == "-50+50=0" )

	{

		alert("Correct!");

	}

	else

	{

		alert("Nope, that's not right.  Be sure to enter you answer as an equation like 5+5=10");

	}

	return false;

}



function exponents_check1()

{

	if(document.forms[0].elements[0].options[3].selected &&

	   document.forms[0].elements[1].options[1].selected &&

           document.forms[0].elements[2].options[2].selected &&

	   document.forms[0].elements[3].options[0].selected  )

	{

		alert("Yes: All letters have been properly readdressed");

	}

	else

	{

		alert("If the letters aren't properly readdressed, the customers will get angry!");

	}

}	



function exponents_check2()

{

	if( eval(document.forms[0].elements[5].value) == 4096 )

	{

		alert("Correct!");

	}

	else

	{

		helpwin=window.open( "exphelp.html", "", "width=350,height=350" );

	}

}



function exponents2_check()

{

	if( eval(document.forms[0].elements[0].value) == 1536 )

	{

		alert("Correct!");

	}

	else

	{

		alert("Nope, that's not quite right.");

	}

	return false;

}	



function identity_check()

{

	if(eval(document.forms[0].elements[0].value) == 1)

	{

		alert("Correct");

	}

	else

	{

		alert("Wrong.  Hint:  Look at the subtle blue picture right in front of you.");

	}

	return false;

}