Why Doesn't the U.S. Use the Metric System, Why Fingernails on Chalkboards Make Us Cringe & More

In today's compilation video, we're covering a myriad of Whys, from Why the United States doesn't use the metric system, why fingernails on chalkboards make us cringe, why we have moles on our bodies, why doesn't the heart get tired like other muscles, and much, much more.

0:00 Why Doesn’t the United States Use the Metric System?
20:55 Why Does the Sound of Fingernails on a Chalkboard or Scraping a Plate Make Us Cringe?
35:09 Why Do We Have Moles All Over Our Bodies and What Do They Do?
42:55 Why Doesn’t the Heart Get Tired and Need to Rest Like Other Muscles?
54:25 Why Do Some People Think the Human Soul Weighs 21 Grams?
1:06:14 Why Do the Eyes in Some Paintings Follow You Around the Room?
1:11:17 Why Does Soda Taste Significantly Better When Carbonated vs. Flat?
1:14:01 Why Do We Get Allergies?
1:27:33 Why You Sometimes Get a Lump in the Back of Your Throat When Sad and Why We Cry
1:32:44 Why Coffee Makes You Poop
1:40:14 Why Can’t People Smell Themselves?