This is normally a $15 value, free for the week!! BE sure to sign up (free) for their newsletters which remind you of the free weekly freebies (not to mention it will sometimes include links to "hidden" freebies!!!
Normally I do not share those here since I am sure everyone gets them already BUT this one was good!!
Bite Sized Physics: Force
A Blessed Day of Memory to You and Yours
21 minutes ago