配平下列化学方程式:
(1) ____ N2+____ H2____ NH3
(2) ____ C2H6+____ O2____ CO2____ H2O
(3) ____ Al2O3____ Al+____ O2↑
(4) ____ C6H12O6+____ O2____ CO2____ H2O.
①把酒话桑麻
②大庇天下寒士俱欢颜
③塞下秋来风景异
④谁道人生无再少
甲队有x人,乙队有y人,若从甲队调出20人到乙队,则甲队人数是乙队人数的一半,可列方程____
—It ________ takes 20 minutes to get there by bus.