Please try this activity:
Tell me if I have made mistakes or omissions, or any ideas for improvement.
There is only a single spelling error. Almost half way down the page "Amd."
To really investigate those stars would require a good sketcher type program. I quickly made a big mess with pen and paper.
What is the reason why for difference between the 6 and 7? Is it because they composite and prime?
If it ain't broke, fix it until it is.
A number by itself is useful, but it is far more useful to know how accurate or certain that number is.