What did the trapped miners eat to survive?
A. Two teaspoons of tuna, biscuit and a sip of milk every two days.
B. Three teaspoons of tuna, biscuit and a sip of milk every two days.
C. Two teaspoons of tuna, biscuit and a sip of milk every day.
D. Three teaspoons of tuna, biscuit and a sip of milk every day.
查看答案
According to the woman, who are the real heroes in the news item?
A. The ones who lost their lives trying to help their fellow miners.
B. The rescuers.
C. The miners and their families.
D. All of the above.
生态系统的三大功能是什么？
A. 能量流动
B. 物质循环
C. 信息传递
D. 生物繁殖
生态系统的组成包括哪几个部分？
A. 非生物环境
B. 生产者
C. 消费者
D. 分解者
生态系统的概念最初是由法国植物生态学家A. G. Tansley提出来的。（ ）
A. 对
B. 错
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