True for #1. False for he rest of them.

is the second or third Pythagorean triple on the list, which gives us the answer directly.
But if we didn't know that, let x be the short leg:




Rejecting the negative root, x=5, other side 12, the Pythagorean triple we found.
Part one is 11 1/8.
part two is 4 7/40.
I think it's square and hexagon.