[填空题]How much has China reduced its population since 1970
China has already cut its rate of population growth by ______.

[填空题]How much has China reduced its population since 1970 China has already cut its rate of population growth by ______.

[单项选择]How much seawater has been sprayed into the Fukushima Daiichi nuclear reactors to keep them cool More (31) than the number of tons of water is the amount of sea salt that was (32) in the reactors: ninety-nine thousand pounds (33) in reactors NO. 2 and 3, and fifty seven thousand in reactor No.1, according to the Times. (34) one might suppose, it is not good for any sort of (35) to have that much salt in it. During the Berlin Airlift, one of the biggest challenges was carrying salt into the city: no matter how it was (36) , it always seemed to get into and (37) the planes’ engines. (And yet the city needed salt to survive. ) And it is not good for nuclear reactors; the heat and the way that it came in, on water, meant that it (38) and crystallized around the uranium fuel rods. From the Times:
Crusts insulate the rods from the water and allow them to (39) up. If the crusts are thick enough, they can bloc