document.onload = function () {
    document.getElementById('contactChoice').addEventListener('change',toggleCallTime, false);
}
function toggleCallTime() {
    if(document.getElementById('contactChoice').value == "Phone") {
        document.getElementById('timeToCall').style.display = 'block';
    } else {
        document.getElementById('timeToCall').style.display = 'none';
    }
}