[tex]a-the\ sides\ of\ the\ square\\\\A_{\fbox{}}=a^2;\ A_{\fbox{}}=8100ft^2\\\\a^2=8100ft^2\\\\a=\sqrt{8100ft^2}\\\\a=90ft\\---------------\\The\ diagonal\ of\ the\ square:d=a\sqrt2\\------------------\\The\ distance\ from\ home\ plate\ to\ second\ base:\\\\d=90\sqrt2\ ft\approx(90\times1.414)ft=\boxed{127.26ft}[/tex]