题目内容：

    Circles can be found everywhere in the natural world, but with no exact way to measure(测量) them they are very mysterious and might never be completely understood. When you take the distance around a circle and divide it by the distance across a circle, you will always get Pi. While Pi is about 3.14 when rounded, it is endlessly long. With the help of computers, mathematicians(数学家) have been able to work Pi out to over a trillion decimal places(小数点后万亿位). This makes Pi mysterious, even to the most famous mathematicians.

Pi Day is celebrated on March 14, since the way we write this date, 3/14, looks just like Pi when rounded. In 2009, U. S. Congress voted to formally make March 14 Pi Day. Certain parts of the world—places where March 14 is written as 14/3—will instead celebrate Pi Approximation Day which takes place on July 22nd because of the division(除法) result of 22/7.

Pi has appeared in movies, comics, music, and more. “In modern movies, any time the filmmaker wants to create a sense of mystery, the symbol Pi is used,” says Blatner. People also love working to remember the digits(数位) of Pi and competing against others to see who can remember most. The Guinness World Record for remembering the most digits of Pi is held by Lu Chao of China, who successfully remembered Pi to nearly 67,000 decimal places.

Above all, Pi Day is about having fun with the number, according to Blatner. People will celebrate Pi Day by eating pie and throwing pie, and with fun Pi-related games. Princeton, New Jersey holds a series of Pi-related festivities. Events this year include a surprise birthday party for Albert Einstein whose birthday also falls on March 14, and a “Walk a Pi Event” where participants will walk 3.14 miles together. Just like the number itself, the possibilities for Pi Day are truly endless.

1.What makes Pi mysterious?

A. Ways to divide a circle B. Ways to use it when rounded

C. Being unable to write it as an expression D. Its endless decimal places

2.Why is Pi Day celebrated in some places on July 22nd?

A. Because it is announce formally B. Because it was corrected originally

C. Because the division result is similar to Pi D. Because that day is easier to remember

3.What is the goal of using Pi in films according to Blatner?

A. To move more viewers B. To call for viewers’ attention

C. To make the films more frightening D. To add something mysterious to the film

4.What can we learn from the text?

A. Lu Chao is the first Chinese to recite Pi

B. Many states in the USA celebrate Pi day on July 22nd

C. There are many different events to celebrate Pi Day in the world

D. Scientists will try their best to work out the digits of Pi thoroughly