题干

香豌豆中,当C与R两个显性基因都存在时,花呈红色。甲、乙两株红花香豌豆分别与基因型为ccRr的植株杂交,子代中开红花比例分别为3/8、3/4;若让甲、乙红花香豌豆分别进行自交, 各自后代红花香豌豆中纯合子分别占 (   )

A:1/9、1/3

B:1/4、1/9

C:1/2、1/3

D:3/4、1/4

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A

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请用适当的词完成下面的短文, 补充所缺的单词。每个空只能填写一个形式正确,意义相符的单词。

    If you pay a visit to Liu Hasheng's restaurant in Harbin, you will find 18 robots there. They are ready to serve you and ____ sure that your dining experience is perfect. After the visit, you can tell others that robots serving customers isn't a dream any more.

    It's wonderful to see ____ the 18 robots work in the restaurant. The wonder starts when you walk in. You ‘ll see a robot come up and say, "Earth person, hello! ____ to the Robot Restaurant." When you have ordered your ____, the robots in the kitchen begin to do the cooking. After the food is ____, a robot waiter will glide(滑行) out of the kitchen to serve you with the meal you've ordered. And as customers enjoy their delicious food, a robot ____lovely songs for them.

    You may ask, "Where did all these robots come ____?" Liu said they were designed(设计) and ____ by the Harbin Haohai Robot Company. Liu said he invested(投资) 5 million yuan in the restaurant, with ____ robot costing 200,000 yuan to 300,000 yuan. And the whole robot team is managed by the workers in the computer room.

    After a busy day, all the robots will go for a "meal", which is electricity. After 5 hours, the robots can continue their work for a day. The restaurant now provides a menu ____ more than 30 dishes(菜肴), and the average(平均) cost for a dinner is about 40 to 50 yuan. Do you want to go and have a try in this restaurant?