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向50mL 稀H2SO4与稀HNO3的混合溶液中逐渐加入铁粉,假设加入铁粉的质量与产生气体的体积(标准状况)之间的关系如图所示,且每一段只对应一个反应。下列说法正确的是

A:开始时产生的气体为H2

B:AB段发生的反应为置换反应

C:所用混合溶液中c(HNO3)=0.5 mol·L—1

D:参加反应铁粉的总质量m2=5.6g

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D

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    Humans and gorillas shared evolution for 23 million years. Their paths separated only six million years ago. Research on how gorillas communicate can help us understand human language development.

    Understanding how the brain works helps us see a connection between language development and non-verbal signs. These signs or movements include things like the way we move our hands or bodies or the different expressions our faces have in different social situations. A new study on gorillas showed that the right side of the body is controlled by the left part of the brain and it is also the location for language development.

    Two cameras were used to film all of one ape's movements. One of the first results was that gorillas use their right hands more when they are doing actions with their heads or mouths at the same time. This shows that there is a connection between how our brain works and the reason we use one side of our body more than the other. In addition, we can use the results of the study and our knowledge about brains to help us understand more about how language first developed in humans.

    Dr Forrester, who did the study, says the results can be useful in other ways, such as understanding language development in children. For example, some children have serious illness called “autism” which can stop them communicating normally with people. It might be possible to use the same study method to find out which children have this illness when they are very young. Doctors will then be able to start treatment early.