A lot of people live by the beach. Maybe you do! In fact, about 40% of the people in thewhole world live in cities close to the coast. But there's just one problem, the sea levels arerising. This is happening because of global warming and people not taking care of the planet.Wild animals and people who live close to the sea might not have homes in 10, 20, or 30 years.And there are a lot of people who live near the oceans! What can we do about this?       One company is trying to build the world's first city on the water. A floating city! The citieswill be made up of floating islands that can easily attach to more floating islands. Attach sixfloating islands together and that makes a small floating city where 10,000 people can live.They also want to make these floating cities self-sustainable.      To do this, people on these islands need to collect water and grow enough food foreveryone. So, one entire island could be used for farming! The cities will also need energy, andthe company hopes the islands can get that from the sun and wind. They will also have to thinkcarefully about how to handle garbage and make everything reusable or recyclable.       It won't be easy, but maybe one day in the future, floating cities can be places where a lotof people live. close to 接近，靠近 attach (v.) 連接，綁self-sustainable (adj.) 自給自足的
【題組】47.What percentage of all people live close to the sea?
(A) 7%
(B) 99%
(C) 40%