A、She went to a concert on her 17th birthday. B、She got the certificate of a concert promoter. C、She arranged a jazz concert at

Good morning. Now, I’d like to begin today’s lecture with a story.
    Late in January 1975, a 17-year-old German girl called Vera Brandes walked out onto the stage of the Cologne Opera House.(16)This was the most exciting day of Vera’s life. She was the youngest concert promoter in Germany, and she had persuaded the Cologne Opera House to host a late-night concert of jazz from the American musician, Keith Jarrett. 1 400 people were coming. But there’d been a mistake. The opera house had provided the wrong piano. A few hours later, Vera still couldn’t get a new piano. But because of her sincerity and her begging, Jarrett did indeed step out onto the stage of the opera house: he sat down at the unplayable piano and began. Within moments it became clear that something magical was happening. Jarrett tried to make the best from the unsuitable piano and it turned out to be an electrifying performance. It somehow has this peaceful quality, and at the same time it’s full of energy, it’s dynamic. And the audience loved it.
    Some theories of cognitive psychology can be found from the story.(17)We’ve actually known for a while that certain kinds of difficulty, certain kinds of obstacle, can actually improve our performance. For example, the psychologist Daniel Oppenheimer, a few years ago, teamed up with high school teachers. And he asked them to reformat the handouts that they were giving to some of their classes. So the regular handout would be formatted in something straightforward. But half these classes were getting handouts that were formatted in something sort of intense. Now, these are really ugly fonts, and they’re difficult fonts to read. But at the end of the semester, students were given exams, and the students who’d been asked to read the more difficult fonts, had actually done better on their exams, in a variety of subjects.(18)And the reason is, the difficult font had slowed them down, forcing them to work a bit harder, to think a bit more about what they were reading, to interpret it... and so they learned more.
    So, sometimes, we do need to deal with the unexpected difficulties, and we need to try to read the ugly fonts. These things help us. They help us solve problems: they help us be more creative.
16. What makes the day in January 1975 the most exciting day of Vera Brandes’ life?
17. What is the theory that lies behind the story of Vera and Keith?
18. Why do students who get handouts with ugly fonts perform better in exams?