SUMA
<script type="text/Javascript">
    var a = parseFloat(prompt("Podaj A"));
    var b = parseFloat(prompt("Podaj B"));
    var c = parseFloat(prompt("Podaj C"));
    var suma = a+b+c;
    alert(suma);
</script>


POLE
<script type="text/Javascript">
    var r = parseFloat(prompt('Podaj promien'));
    var pole = Math.PI*Math.pow(r,2);
    var obw= 2*Math.PI*r;
    alert("Pole = "+pole+" Obw = "+obw);
</script>


MIN/MAX
<script type="text/Javascript">
    var a = parseFloat(prompt("Podaj A"));
    var b = parseFloat(prompt("Podaj B"));
    var c = parseFloat(prompt("Podaj C"));
    var min = Math.min(a,b,c);
    var max = Math.max(a,b,c);
    alert('Min = '+min+" Max = "+max);
</script>