text: #!/usr/bin/node
  // 07-exports-function.js
  
  var pi = Math.PI;
  
  module.exports = function(radius) {
    function diameter() {
      return 2 * radius;          
    }
  
    function circumference() {
      return pi * diameter();
    }
  
    function area() {
      return pi * Math.pow(radius, 2);
    }
  
    return {
      area: area,
      circumference: circumference
    };
  }
  
  console.log('\n07-exports-function\n', module);
  
  