A、186282 miles per second. B、8. 3 million miles per second. C、10000 miles per microsecond. D、1 billion miles per second. A

It takes 8. 3 minutes for the sun’s light travelling at 186 282 miles a second to reach the earth. At that speed, light could travel around the earth seven times in one second. The sun looks yellow-gold, because we’re viewing it through the earth’s atmosphere. Judging from its surface temperature, the sun’s color is probably closer to white. The temperature of the sun at its core is around 73 million degrees F. It takes 50 years for this energy to reach the sun’s surface, where we can see it as light. The English astronomer James Jeans once figured that if you placed a piece of the sun’s core, the size of the head of a pin, on earth, its heat would kill a person 94 miles away. The temperature of the sun’s photosphere, the part that sends us light, is about 10000 degrees F. The sun contains 99. 9％ of the matter in our solar system. The sun produces more energy in one second than human beings have produced in all of our history. In less than a week, the sun sends out more energy than we could make by burning all the natural gas, oil, coal and wood on the earth. The earth receives one two-billionth of the sun’s power. With every passing day, the sun is losing energy, but it still has about 5 billion years of life left.
    Questions 9 to 11 are based on the passage you have just heard.
    9. According to the speaker, what is the travelling speed of the sun’s light?
    10. According to the speaker, what is probably the sun’s actual color?
    11. What is happening each day to the sun?