text: function reverseWords(sentence) {
    return sentence.split(' ').map(word => {
      if (word.length >= 5) {
        return word.split('').reverse().join('');
      } else {
        return word;
      }
    }).join(' ');
  }
  
  reverseWords('Professional');             // "lanoisseforP"
  reverseWords('Walk around the block');    // "Walk dnuora the kcolb"
  reverseWords('Launch School');            // "hcnuaL loohcS"