题目

生日蛋糕中的奶油含有对人体有害的反式脂肪酸，其化学式为C18H34O2。下列说法正确的是( ) A. 反式脂肪酸是氧化物 B. 反式脂肪酸由碳、氢、氧三种元素组成 C. 反式脂肪酸由54个原子构成 D. 反式脂肪酸中碳、氧元素的质量比是9∶1 答案：B 【解析】氧化物是由两种元素组成，且其中一种元素是氧元素的化合物，反式脂肪酸由碳、氢、氧三种元素组成，A错误，B正确；反式脂肪酸由分子构成，一个反式脂肪酸分子由54个原子构成，C错误；反式脂肪酸分子中碳原子与氧原子的个数比为9∶1，由于不同原子的质量不同，所以元素的质量比不等 听力 第一节：(共5小题；每小题1.5分，满分7.5分) 1．When did the man go to the restaurant? A．Yesterday． B．Last month． C．Last week． 2．What is Neil doing? A．talking to the boss in his office． B．Doing his work in his office． C．Making a call to the boss． 3．What will the man probably do? A．Leave work early． B．Work overtime． C．Start work early 4．How does the woman feel about the man’s words? A．Excited． B．Frightened C．Surprised 5．Which of the following countries does the woman probably want to go to? A．A China． B．France． C．Australia． 第二节：(共10小题；每小题1.5分，满分22.5分) 听第6段材料，回答第6至第7题。 6．What do the man’s parents do? A．Salespeople． B．Restaurant owners． C．Supermarket owners． 7．What did the man sell to the students? A．Books． B．Meals． C．Clothes 听第7段材料，回答第8至第10题。 8．What color of overcoat does the woman like? A．The black one． B．The silver white one． C．The silver grey one． 9．What does the woman think of the overcoat? A．It is of bad quality． B．It is very expensive． C．Its style is old 10．Who is the man probably? A．A salesman． B．The woman’s husband． C．The woman’s friend． 听第8段材料，回答第11至第13题。 11．What can we know about Betty? A．She works in a Mexican hotel． B．．She has been to Mexico C．She is a guide 12．What was the weather like in Mexico City? A．Cool． B．Warm． C．Cold． 13．What does Betty suggest to the woman? A．Putting off their trip． B．Reading the guide book． C．Making early plans． 听第9段材料，回答第14至第16题。 14．When did the woman dream of becoming a singer? A．When she was 12 years old B．When she was 5 years old． C．When she met Rene 15．What can we learn from the conversation? A．The woman’s parents were singers． B．The woman’s father sent the tape to Rene C．The woman’s parents ran a piano bar． 16．How did Rene feel when he first heard the woman singing? A．He was moved． B．He was surprised． C．He was disappointed． 听第10段材料，回答第17至第20题。 17．What will the listeners do after the talk? A．Make a campfire B．Take a guided tour． C．Go for a nature walk． 18．When did the National Park Service begin? A．In the early 1800s． B．In the late 1800s． C．In the late 1700s． 19．What does the speaker say about the national park? A．It was declared the first national park in the world． B．A large group of people found the land now called Yellow Stone． C．All the parks were managed by the National Park Service before 1916 20．What is one of the speaker’s duties? A．Protecting the plants． B．Guiding nature walks． C．Answering the visitors’ questions．