题目内容
计算机病毒是一种（）
查看答案
搜索结果不匹配？点我反馈
更多问题
在CIDF体系结构中，以文件或数据流的形式出现的是（）
调角与调幅比较，其突出优点是（），但缺点是（）
Fifty years ago,zoos were places where people could go to see animals from many parts of world.The animals lived in cages that were easy to keep clean.However,for the animals,the cages were small and impossible to hide in.Although the zoo keepers took good care of them,many of the animals did not feel comfortable,and they often become ill.In modern zoos,people can see animals in more natural conditions.The animals are given more freedom in larger places so that they can live as they could in nature.In an American zoo,visitors can walk through a huge special cage that is filled with trees,some small animals and many birds.Some zoos have special places for visitors to watch animals that live in the desert or under water.Some other zoos have special places for animals that live in cold conditions like the bear from Arctic.Modern zoo not only show animals,but also keep and save rare animals,for the reason the grandchildren of today’s visitors will still be able to enjoy watching these animals. In some modern zoos,visitors can see（）.
下列物质属于弱电解质的是（）
微信支付 
支付宝支付