“123456789101112…282930”是一个多位数,从中划去40个数字,使剩下的数字(先后顺序不能变)组成最大的多位数,这个最大的多位数是 ____ .
长颈鹿是世界上个子最高的动物,个子高了血压也要高,所以长颈鹿又是世界上血压最高的动物,雌长颈鹿平均高度约4.3 m,血液密度约1.05×103 kg/m3,当长颈鹿的心脏收缩把血液压到比心脏高3.4 m的脑子里去时,压强至少是____Pa。(g取10 N/kg)
人体中二氧化碳浓度最高的地方是( )
完形填空
(1) is an American girl. (2) name is Helen. And this is Mike. (3) is an English boy. Mike can (4) his name. Kate can sing ABC song. Mike's home phone number is 658-4323. He can (5) Kate at 954-3643. They (6) friends now.