04:05 Design, Engineering & Technology How to spot a counterfeit bill Lesson duration 04:05 1,036,679 Views
04:53 Design, Engineering & Technology What's the difference between accuracy and precision? Lesson duration 04:53 5,963,893 Views
04:57 Design, Engineering & Technology Camera or eye: Which sees better? Lesson duration 04:57 1,656,031 Views
04:03 Science & Technology The effects of underwater pressure on the body Lesson duration 04:03 665,430 Views
04:51 Philosophy & Religion What did democracy really mean in Athens? Lesson duration 04:51 1,486,982 Views