题目内容：

    UK-based swimming pool manufacturer (制造商) Compass Pools has announced plans for the world’s first 360-degree infinity (无限) pool. Titled Infinity London, the pool would contain 600,000 liters of water, and would sit at the top of a 55-story hotel.

According to Compass Pools’ plan, the pool would feature transparent (透明的) walls and floor, offering views across London’s skyline and down into the hotel below. These walls would be made of cast acrylic, a material chosen to make sure that the material is completely clear.

The main problem with designing the pool was how to make sure entry or exit from the pool without affecting the view. Speaking about this design, Compass Pools’ technical director and designer Alex Kemsley explained，“Normally a simple ladder would suffice, but we didn’t want stairs on the outside of the building or in the pool as it would spoil the view – and obviously you don’t want 600,000 litres of water running down through the building either. The solution is based on the door of a submarine, coupled with a rotating spiral (螺旋的) staircase which rises from the pool floor when someone wants to get in or out.”

Take a look at early models of how the pool might look in the gallery above. At present, no contract has been made but building work could begin as early as 2020.

1.What does the underlined word “suffice” in Paragraph 3 mean?

A.Solve the problem. B.Beautify the pool.

C.Add to the difficulty. D.Make sure of safety.

2.How can swimmers get in the pool?

A.By stepping onto a simple ladder in the pool.

B.By taking a lift of the building below the pool.

C.Through a rotating spiral staircase in the center of the pool.

D.Through a submarine door and a staircase.

3.Which is the best title for the text?

A.The secret of the world’s first 360-degree infinity pool

B.World’s first 360-degree infinity pool is set to open in London

C.UK-based swimming pool manufacturer Compass Pools meet problems

D.Enjoying ourselves in the sky is never impossible