Hello,friends! My name is Jack.I am a Chinese boy.My favourite food is chicken.I like beef noodles,too.I don't like fish but egg is OK.Potatoes are my favourite vegetable.My favourite fruit is bananas.They are so sweet.
现有一个圆心角为90°,半径为10的扇形纸片,用它恰好卷成一个圆锥的侧面(接缝忽略不计),则该圆锥的底面半径为( )
读课文《我是最弱小的吗》,按课文内容填空。
森林里的景色是那么____,空气是那么____。