22:22 duration 22 minutes 22 seconds
GEB4935 HSA4938 - Lesson 10_ch 9
21:38 duration 21 minutes 38 seconds
GEB4935 HSA4938 - Lesson 11_ch 10
21:41 duration 21 minutes 41 seconds
GEB4935 HSA4938 - Lesson 05_ch 3