Cacher is the code snippet organizer for pro developers

// Program File: areaOfRing2.js

/* R: radius of outer disk
   r: radius of inner disk
   return: area of the ring
 */
function areaOfRing(R, r) {
  return Math.PI * (R ** 2 - r ** 2);
}

//TESTS =================================>>

//declare the input and output variables
let outerDiskRadius, innerDiskRadius, area;

outerDiskRadius = 10;
innerDiskRadius = 8;
area = areaOfRing(outerDiskRadius, innerDiskRadius);

//output results on console(note backticks)
console.log(`outerDiskRadius = ${outerDiskRadius} 
innerDiskRadius = ${innerDiskRadius}
area = ${area}`);

outerDiskRadius = Number(prompt('enter outer radius'));
innerDiskRadius = parseFloat(prompt('enter inner radius'));
area = areaOfRing(outerDiskRadius, innerDiskRadius);

//output results in an alert(note backticks)
alert(`outerDiskRadius = ${outerDiskRadius} 
innerDiskRadius = ${innerDiskRadius}
area = ${area}`);