A：Because he was too busy to go to the bookstore.
B：Because the bookstore closed before he arrived.
C：Because the books were sold out before he arrived.
2010年上海世博会上，中国馆展出了电子动态版的《清明上河图》，这表明我国哪一技术的高度发展（ ）
-________ is it from the bus stop to the train station? -Two kilometers.
列竖式计算。
①44×22= ②12×12= ③33×31=
④23×13= ⑤43×22= ⑥14×12=
