2011年世界园艺博览会于4月28日——10月22日在陕西省的省会西安市举办。家住淄博的小明同学想利用暑假同父母乘火车前去观看。那么，他们的乘车线路应该是胶济线—

铁在高温下能与水蒸气反应，生成四氧化三铁与氢气，该反应中还原剂是（　　）

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   Mike is seven years old now and begins(开始) to go to school. His father is a driver and takes him to school in his car. Mike studies very hard(努力地) and all his teachers like him very  much.
   One day, Miss White teaches the students to count from one to ten. Mike can count them. Miss White is happy and asks him, “How many people(人) are there(有) in your family, Mike?”
“Two, Miss White, ” Mike says.
“Who are they?”
“My father and mother.”
“Oh?” Miss White is surprised(吃惊地). She says, “But I think there are three people in your family—your father, your mother and you. Am I right?”
“No. I'm not at home now. I'm at school, you know!” Mike says.