function randNum() {
    return Math.random() * 1.5 + 4;
}
function unknownString(r) {
    var num = r / 60.05;
    
    return "u1," + num;    
}
var unknown = randNum()
unknown_string = unknownString(unknown);

var attempt = 1;
var attempts = 1;
function check_first() {
    var user = document.getElementById('conc1').value;
    if (user == null || user == '') {
        alert("Please enter your answer before submitting.");
        return false;
    }
    var correct = false;
    var answer = unknown / 60.05 * 10;
    if (relativeError(answer, user,0.01)) { correct = true; }
    
    
    if (correct) {
        message = "Correct! Good job.";
        second.activate();
        attempt = 1;
    } else if (attempt < 3) {
        message = "You are wrong, but you still have " + (3 - attempt) + " attempt"+(attempt == 2? "": "s")+" left.";
    } else {
        message = "Incorrect. The correct answer was "+format_sig(answer,3)+" M. That was your 3rd attempt, please refresh and try again.";
        first.deactivate();
    }
    attempt++;
    
    first.setFeedback(message, attempt);
    
    return false;
}

function check_second() {
    var user = document.getElementById('massp1').value;
    if (user == null || user == '') {
        alert("Please select your answer before submitting.");
        return false;
    }
    var correct = false;
    var answer = unknown;
    if (relativeError(answer, user,0.01)) { correct = true; }
    
    
    if (correct) {
        message = "Correct! Good job.";
    } else if (attempts < 3) {
        message = "You are wrong, but you still have " + (3 - attempts) + " attempt"+(attempts == 2? "": "s")+" left.";
    } else {
        message = "Incorrect. The correct answer was "+format_sig(answer,3)+"%. That was your 3rd attempt, please refresh and try again.";
        second.deactivate();
    }
    attempts++;
    
    second.setFeedback(message, attempts);
    
    return false;
}