[tex]\displaystyle\bf\\1)\\a)\\L_c=2\pi R=2\pi\times5\sqrt{2}=10\pi\sqrt{2}~cm\\\\b)\\A_d=\pi R^2=\pi\times\Big(5\sqrt{2}\Big)^2=\pi\times25\times2=50\pi~cm^2\\\\2)\\Aria=\pi R^2=36\pi\\\\R^2=36\\R=6~cm\\L_H=R=6~cm\\P_H=6L_H=6\times6=36~cm\\\\3)\\Diagonala~dreptunghiului = \sqrt{3^2+4^2}=\sqrt{3^2+4^2}=\sqrt{25}=5~cm\\Diagonala~dreptunghiului = Diametrul~cercului.\\\\R=\frac{D}{2}=\frac{5}{2}=2,5~cm\\\\L_c=2\pi R=2\times 2,5\times\pi=5\pi~cm[/tex]
