正方形的面积＝.X3g,N9k7h1U9i9{5?4D-C(L6W.u×8r9l9o,R([，正方形的周长＝)r,T+R-O(f4j0[8S/{*y,{(l(\2t×:i(h7u){)?-P3e(R-n2h*S3V:\9e;F;m4[0E*Z