阅读短文，选择正确的答案。
    A little mouse thought he was the tallest and strongest animal in the world. His mother said to him, "Don't say that in front of an elephant. He doesn't like that." The little mouse didn't listen to his mother. He went out to look for the elephant, but he didn't know who the elephant was. He asked an ant(蚂蚁) first, "Are you an elephant?" "No, I'm not," said the ant. "An elephant is much bigger than I am." Suddenly(突然), he saw four big trees. "Let me climb up(爬上) a tree. Then I can see where the elephant is," said the little mouse. "Get down! Get down!" someone shouted(喊) to him. "I'm the elephant. Go and climb that tall tree nearby. Then you can see me." "Now, I see. The elephant is the tallest and strongest animal in the world," said the little mouse.

计算 | -1-(-) |-| -- | 之值为何？

一个质量为100g的铁块受到的重力大小为____N（g取10N/kg）。

右图所示的细胞可能是（    ）