题干

古语道:“人要实、火要虚”,此话的意思是:“做人必须脚踏实地,事业才能有成”,燃烧固体燃料时需要将其架空,燃烧才能更旺.从充分燃烧的条件看,“火要虚”的实质是(   )

A:增大可燃物的热值

B:提高空气中氧气的含量

C:降低可燃物的着火点

D:增大可燃物与空气的接触面积

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答案(点此获取答案解析)

D

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    When I was little, my mother began selling flowers in Camden Market. She couldn't1me at home on my own, 2I had to go to the market with her.

    3, I didn't have to do anything. I just sat there, and my mother told me jokes and stories so I didn't get 4.When I got older, I gave my mother a hand and I really enjoyed it.

    Then one year, my grandma gave me a book for Christmas. It was all about making candles and I loved it. I was 14, and I didn't have to go to the market5because my mother could leave me at home on my own. I6my free time making candles of all shapes and sizes. I made7them.

    One day, my mother was ill, so I had to go to the market on my own. I decided to8some candles with me and see9I could sell them. They10in 20 minutes! The next week, my mother gave me some money to buy some wax (蜡) to make more candles. They were sold out really quickly, too.

    Ten months later, we decided11flowers. My mother and I couldn't make enough candles during the week, so some of my friends started to help us. I paid them one pound12every candle, and we 13sell them for three or four times. It was fun and my friends worked with me in the market.

    At the age of 22, my uncle14me some money and I opened my first shop in Portobello Road. Since then, I've15looked back, even in difficulties. In the first store, we only sold candles, but now we sell everything from the designer, furniture to paintings. Oh, and candles, of course.