根据短文回答 16～22 题。
Norwich
Norwich, the capital of the part of Britain known as East Anglia, has been existence for more than two thousand years It began as a small village beside the River Wensum．At the time of the Norman invasion in 1066 it had grown to become one of the largest towns in England.
With two cathedrals and a mosque (清真寺), Norwich has long been a popular centre for various religions．The first cathedral was built in 1095 and has recently celebrated its 900th anniversary, while Norwich itself had a year of celebration in 1994 to mark the 800th anniversary of the city receiving a Royal Charter．This allowed it to be called a city and to govern itself independently.
Today, in comparison with places like London or Manchester, Norwich is quite small, with a population of around 150,000, but in the 16th century Norwich was the second largest city of England．It continued to grow for the next 300 years and got richer and richer, becoming famous for having as many churches as there are weeks in the year and as many pubs as there are days in the year.
Nowadays, there are far fewer churches and pubs, but in 19 the University of East Anglia was built in Norwich．With its fast-growing student population and its success as a modern commercial centre (Norwich is the biggest centre for insurance services outside London), the city now has a wide choice of entertainment: theatres, cinemas, nightclubs, busy cafes, excellent restaurants, and a number of arts and leisure centers．There is also a football team, whose colours are green and yellow．The team is known as 'The Canaries (金丝雀)', though nobody can be sure why.
Now the city's attractions include another important development, a modern shopping centre called 'The Castle Mall'．The people of Norwich lived with a very large hole in the middle of their city for over two years, as builders dug up the main car park．Lorries moved nearly a million tons of earth so that the roof of the Mall could become a city centre park, with attractive water pools and hundreds of trees．But the local people are really pleased that the old open market remains, right in the heart of the city and next to the new development．Both areas continue to do good business, proving that Norwich has managed to mix the best of the old and the new．
第 16 题 The River Wensum flows by Norwich.（ ）