mechanics of material >>> calculate the failure stress

1.  Watch this video:

https://youtu.be/vPBM0g9usMs

Calculate the failure stress (as accurately as possible given what they tell you in the video) for the bar in the video.  How does it compare with the steel values given in the back of the book?

2.  Watch this video:

https://youtu.be/fwCNzID9CeE

Give one or two sentences about the error in the script related to material properties (hint: watch :22 - :36).  Congratulations, you've out-geeked the geeks!

the book:

mechanics of material russel C, 9th