431800－294000＝____

782003＋167209＝____

在半径为1的圆中，长度等于$\sqrt{2}$的弦所对的圆心角是 ____度．

删除：把多余的词用斜线（\）划掉。

增加：在缺词处加一个漏字符号（∧）,并在该词下面写出该加的词。

修改：在错的词下划一横线,在该词下面写出修改后的词。

注意：1）每处错误及修改均仅限一词。

2）只允许修改10处,多者（从11处起）不计分。

    Today I was going home by bike where a little dog ran to me. I stopped in time avoid hitting the dog. Luckily, it was not injuring, but lay on the ground. I came nearer and touched its side gently. It jumped to its foot quickly and stared at me in a friendly way. Seeing nothing seriously, I was about to leave, but the dog stops me by biting my trousers. So I wanted to adopt to the dog but it was unfair for its master. Just then, the woman came, saying that the dog was his and that I could take it away. Thus I got a lovely pet and I was very grateful for this kind woman.