A

    No one knows what our life will be like in the future. Here are some children's1

Cindy:In the future, people will have more holidays. They will2a lot of time traveling (旅行) around the world. Maybe some families will go to the moon

3their holidays.

    Gary:I think the earth will be more crowded and polluted. Maybe some people will4their houses on other planets.

    Sarah:Students in the future won't need to go to school and they will study at home. What will happen5students have problems with a subject? They wil

6with a teacher through videoconferencing (视频会议).

    Peter:In the future, people will speak fewer languages. Maybe there will be

7one language in the world. And it will be much8for people to talk with each other.

Laura:Robots will play an important role in our life.9will help humans do all kinds of work.

    These predictions may seem impossible today, but I10they will come true one day because we never know what will happen in the future.

1912年元旦，孙中山在北京宣誓就职，宣告中华民国临时政府成立。
                           

从A沿北偏东60°的方向行驶到B，再从B沿南偏西20°的方向行驶到C，则∠ABC=____ 度．

某校探究性学习小组对一个池塘生态系统中生物摄取的食物成分进行分析，生物之间存在下表所示的食物关系（存在食物关系用“√”表示）请据表回答下列问题：

（1）此池塘生态系统中属于生产者的有____ ；次级消费者有____ 。
（2）此池塘生态系统中共有____ 条食物链，请写出一条包含鱼虫的食物链____ 。
（3）根据表中生物之间存在的食物关系可知，草鱼属于____ 性动物，鲫鱼属于____ 性动物。
（4）假如草鱼的食物全部来自水草，水草体内含有的能量只有10%能够流入草鱼，则草鱼体内的能量每增加1千焦需消耗含____ 千焦能量的水草。鸡粪是优良的鱼类饲料，适量的投入可以给鱼提供食物，从而提高鱼的产量。鸡粪中的碳元素以____ 形式流向鱼。