diff --git a/04 - Array Cardio Day 1/index-START.html b/04 - Array Cardio Day 1/index-START.html
index eec0ffc31d..c78d3b6cb3 100644
--- a/04 - Array Cardio Day 1/index-START.html	
+++ b/04 - Array Cardio Day 1/index-START.html	
@@ -31,29 +31,49 @@
 
     // Array.prototype.filter()
     // 1. Filter the list of inventors for those who were born in the 1500's
+inventors.filter(el => { el.year >= 1500 && el.year < 1600 })
 
     // Array.prototype.map()
     // 2. Give us an array of the inventors' first and last names
+inventors.map(i => `${i.first} ${i.last}`)
 
     // Array.prototype.sort()
     // 3. Sort the inventors by birthdate, oldest to youngest
+inventors.sort((a, b) => a.year - b.year)
 
     // Array.prototype.reduce()
     // 4. How many years did all the inventors live?
+//861
+inventors.reduce((total, i) => {
+  let yearsLived =  i.passed - i.year;
+  return total + yearsLived;
+}, 0);
 
     // 5. Sort the inventors by years lived
+inventors.sort((a, b) => {
+  return (a.passed - a.year) > (b.passed - b.year) ? 1 : -1
+})
 
     // 6. create a list of Boulevards in Paris that contain 'de' anywhere in the name
     // https://en.wikipedia.org/wiki/Category:Boulevards_in_Paris
+Array.from(document.querySelectorAll('li a')).map(el => el.title).filter(title => /de/.test(title))
 
 
     // 7. sort Exercise
     // Sort the people alphabetically by last name
+people.sort()
 
     // 8. Reduce Exercise
     // Sum up the instances of each of these
     const data = ['car', 'car', 'truck', 'truck', 'bike', 'walk', 'car', 'van', 'bike', 'walk', 'car', 'van', 'car', 'truck' ];
 
+data.reduce((total, el) => {
+  if (!total[el]) total[el] = 0;
+
+  total[el] += 1
+  return total
+}, {})
+
   </script>
 </body>
 </html>