请给出五个使用英语的例子，展示在不同情境下“cool”这个词的不同意思或用法。
1. It's cool outside. (表示气温低或凉爽的天气)

2. His new car looks really cool. (表示外观或款式时尚或有吸引力)

3. Be cool, man. Don't get too upset. (表示保持冷静或放松)

4. He thinks he's too cool for school. (表示自大或过分自信)

5. That's a really cool idea. (表示有趣、创新或有益的想法)