①25.35+4.35+2.65-4.35 ②136.8-(10.55+36.8) ③99×56+56
④6.2+5.18+2.8 ⑤98×4.5+2×4.5 ⑥3.63-1.25+17.37-8.75
①456+162=
②※673+587=
③※800-653=
④67×8=
⑤240×5=
⑥409×7=
⑦156+358+144=
⑧890-508+253=
⑨900-283-207=
正方体是一种特殊的长方体.