题目

使用UE软件观察字符串“3-2=1”的内容，如图所示：则字符串“6+8>10”的内码是（ ） A . 36 2B 38 3D 40 B . 36 2B 38 3E 31 30 C . 36 2B 38 3E 3A D . 36 2B 38 3D 31 30 答案：B　　Before trains, most things went by road. But 200 years ago the roads were very bad, and the horses couldn't pull the heavy wagons（动货马车）very fast. Sometimes, when the road was wet, they couldn't pull them at all! When that happened, the driver took flat pieces of wood and put them on the ground under the wheels; then it was easy to pull the wagons, and the horse could do the job very well when the road was flat. When the road was going down a hill, the horse didn't pull the wagon at all, but when the road was going up a hill, it was very difficult to pull the wagon. 　　On the first railways, the horse pulled the train when the road was flat. There was a wagon at the back of the train to carry the horse when the train was going down a hill. There was an engine with a long rope to pull the train when it was going up a hill. But the engine stayed in the same place all the time; it didn't move with the train. The first engines didn't work very well, and they sometimes didn't work at all, but they often helped the horses to climb up the hills. 　　Then Richard Trevithick had an idea. “Let's put the engine on the train,” he said. And that was the first real train. (1) 200 years ago _______. [　　] A．the roads were very good B．the roads were very bad C．there weren't any roads D．there were trains but no roads (2) When the road was flat, __________. [　　] A．the horse pulled the wagon very well B．the horse pulled the wagon very badly C．the horse couldn't pull the wagon at all D．the horse didn't pull the wagon (3) There was a wagon at the back of the train _____. [　　] A．to pull the horse B．to carry the driver C．to carry the horse D．to pull the train (4) The first engines ________. [　　] A．worked very well B．didn't work at all C．didn't help the horses to climb up the hills D．sometimes worked and sometimes didn't work