Workers at the Marine Biological Association (MBA) in England were surprised when a letter to “George Parker Bidder” arrived at their offices. They couldn’t understand why someone was writing to their former president, who had been dead for more than 60 years. It became clearer when the letter was opened. Inside, there was an old postcard. On one side was a series of questions about how the postcard had been discovered.
The postcard was from a bottle dropped into the North Sea more than a century earlier. It was one of just over 1,000 bottles that Bidder had thrown into the sea as part of a study on the movement of water.
Unluckily, the old postcard shows nothing new about the movement of water. All it tells the workers is where it was dropped and where it was found.
A.What happened in between remains a secret! |
B.However, about 400 bottles had probably got lost. |
C.It was then picked up by a woman on holiday there. |
D.On the other were directions on how to mail it back. |
E.Many bottles were discovered within four years of this experiment. |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

