I'm trying to make a BMI Calculator, and to play a video that correlates with the entered BMI. I can't figure out how to do it though. I want the video to only appear when the calculate button is pressed. My script to show the results so far. `<!-- SCRIPT -->

function BMI() {
    var h=document.getElementById('h').value;
    var w=document.getElementById('w').value;
    var bmi=w/(h/100*h/100);
    var bmio=(bmi.toFixed(2));
    if (bmio < 18.5)
    {
    document.getElementById("result").innerHTML="You're Underweight, Your BMI is    " + bmio;
    }
    if (bmio > 18.4 && bmio < 25 )
    {
    document.getElementById("result").innerHTML="You're Healthy, Your BMI is " + bmio ;
    }
    if (bmio > 24.9 && bmio < 30 )
    {
    document.getElementById("result").innerHTML="You're Overweight, Your BMI is " + bmio ;
    }
    if (bmio > 30 )
    {
    document.getElementById("result").innerHTML="You're Obese, Your BMI is " + bmio ;
    }
}

` I don't know where to start, I'm a beginner to this. Sorry if I haven't clarified well enough.