=300×60÷2÷10,
=18000÷20,
=900(棵),
答:这个果园共有果树900棵
下列国家中,蔗糖、香蕉、剑麻、咖啡的产量居世界首位的是( )
Stephen Hawking believes that earth is unlikely to be the only planet life has developed gradually.
蚯蚓、蝗虫、鲫鱼、兔的呼吸器官分别是( )