According to the passage, if there were 500 tons of uranium ore, how many tons of useful uranium-235 could be extracted A: 1 kilogram. B: 10 kilogram. C: 50 kilogram. D: 500 kilogram.

According to the passage, scientists failed to______ A: discover the characteristic of nuclear process B: discover the nature of uranium ore C: save the life of uranium miners D: store nuclear wastes in underwater tanks

下列不属于全新一代奇骏的轮胎规格是（） A: 235/65R17 B: 235/60R18 C: 235/55R19 D: 235/50R20

They have been arrested as suspected drug______. A: abortion B: vector C: uranium D: traffickers

全新RDX标配的轮胎规格为（） A: 235/55R19 B: 245/55R19 C: 235/65R19 D: 235/50R19

The melting point of uranium dioxide is plutonium dioxide A: higher than that of B: the same as C: lower than that of D: similar to

任何中子只要能碰到铀235，都可以引发铀235裂变

您的房间是235房间，在二楼。Your _____________ is 235, on the second floor.

Her studies showed that the effects of the rays were constant even when the uranium ore was treated in different ways. (Para. 5)

实现U—235裂变的方法有（）。 A: 浓缩U—238 B: 不让U—238吸收中子 C: 不让U—235吸收中子 D: 浓缩U—235