for part a I think the length is \(\sqrt{34}\) and I think part b has the same answer

I need help with part c

at least this one showed some of their efforts instead of expecting us to spoonfeed them answers, a rare occurence these days

For part c, after you draw the two segmants from PA and PF, we can see that triangle FPE can fit on GF, while triangle ADP can fit on AB. This creates a third square that is diagonal.