my thanks to everyone ... right now I'm feeling that the world is a pretty great place."

24. What troubled Mike when he was in his first year at college?

A. He couldn't afford his tuition.

B. He failed to find a part-time job.

C. His parents were unwilling to help.

D. His parents had huge debts to pay off.

25. Why did Mike write to Greene?

A. To express his thanks. B. To send his greetings.

C. To ask for help. D. To introduce himself.

26. What can we infer from Paragraph 4 about Mike?

A. His fund needed more donations. B. He became rich and successful.

C. His plan really worked. D. He asked for too much.

27. What's the best title for the text?

A. Pennies for readers B. The one penny college fund

C. Mike's business in college D. The value of education

　　The first lighthouses (灯塔) in America, which were built in the 1710s, used wood or coal as fuel (燃料). By the mid-1700s, American lighthouses began to use oil-burning lamps (灯). The lamps were lit and then placed in a high place so they could be seen from great distances.

　　The trouble with using oil lamps was that only a small percentage of the light produced by the lamp could be seen from the sea. Increasing the amount of light meant burning more fuel, which required bringing more oil to the lighthouse. This was a difficult job for the lighthouse keeper.

　　Many inventors tried different ways to increase the brightness of the light from oil lamps. By the early 1800s, American lighthouses used Argand lamps. Air coming from the base of this lamp made the light brighter. With the addition of a reflector, the Argand lamp became standard in American lighthouses until the 1850s. Ships fifteen miles away could see the light on a clear night.

In 1819, the French government asked scientist Augustin-Jean Fresnel to work on directing more light toward ships. Fresnel, who studied prisms (棱镜), began working