家庭里发生的下列变化中，属于物理变化的是（　　）

增加：在缺词处加一个漏词符号（∧），并在此符号下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1).每处错误及其修改均仅限一词；

2).只允许修改10处，多者（从第11处起）不计分。

    Yesterday, as I was queuing at the checkout at a store, there was an old lady in the front of me in line. She seemed very confusing when the cashier asked her pay US$38. She had about US$5 in her wallet. The cashier told her that she could not buy the items because she didn't have enough money. So, I told the cashier I would pay for that she bought. Afterwards, I paid for all the items. When I got outside, the lady was standing there. While I was talking about her, her daughter appeared. She told me that her mother had Alzheimer's disease. Then she noticed that her mother had three bag of groceries and wondered how she managed to pay for them with enough money. I told her that I had paid for it. The daughter wanted to pay me back, so I refused. I believe make others feel good makes me feel good.

图为某区域7月份等温线分布示意图，当a＞b时，据图分析下列说法正确的是（　　）