题目

八（1）班同学为了解2015年某小区家庭月均用水情况，随机调查了该小区部分家庭，并将调查数据进行如下整理， 月均用水量x（t）频数（户）频率 0＜x≤560.12 5＜x≤10m0.24 10＜x≤15160.32 15＜x≤20100.20 20＜x≤254n 60≤x＜7020.04 请解答以下问题： （1）求出吗、M，n的值，并把频数分布直方图补充完整； （2）若该小区有1000户家庭，求该小区月均用水量超过10t的家庭大约有多少户？阅读理解     Back in the 1970s, the robots were coming for our boring manufacturing (生产) jobs.Now, they're coming for our boring table service jobs.Korean company ITM Technology has developed the restaurant concept around a little robot that fulfills the role of a waiter.Robo Caf? avoids ordering errors, reduces staffing costs greatly for restaurant owners, and even brings the boss all the tips.     Japan is preparing for some very tough times ahead.When its aging population become too old to work, labor is going to be in severe shortage.So inventive technology departments are exploding with really fascinating ideas to take the pressure off when it hits.     To small caf? and restaurant owners, the solution might well look something like Robo Café, a restaurant designed to operate as efficiently as possible with the absolute minimum human workforce possible.The building needs to be designed with small horizontal (水平的) pathways leading from the kitchen to all the tables.A small team of waiter robots can then get around to every table in the house when they're asked to come.Customers can either order orally, or touch a screen on the robot's belly.When the kitchen has finished preparing the food, the robot brings it out to customers.     Dan Carlin talks about the "kitchen of the future ", where everything is automated and the labor is free because you own it.Really, the_kitchen_of_the_future_is actually_the_kitchen of_the_past, when you consider that throughout human history, there have been many examples of slaves working for no pay.     As Carlin points out, today's concept of slavery is mostly restricted to nonhumans.And the ownership of robot labor in a Robo Caf ?type situation will almost certainly prove itself far more economical and dependable than a human workforce once the technology itself becomes mature.Of course, slaves have a worrying habit of rising up against their owners.1. According to the passage, the robots that were invented in the last century could________.A. do some work that people dare not doB. bring lots of fun and profits to their ownersC. do some housework such as table service workD. save people from having to do some boring manufacturing work2. According to the passage, what will a Robo Café-type restaurant be like?A. Most of the work will be done by robots.B. Owners needn't pay for the labour of their employees.C. Robot waiters are designed to serve customers voluntarily.D. The building will be designed for the convenience of customers.3. What does the underlined part in Paragraph 4 probably mean?A. Employees depend on owners of restaurants as before.B. Technology won't change the core of the kitchen.C. Labor free of charge can be used in the kitchen again.D. Labor free of charge is no longer limited to humans.4. The passage is mainly written to________.A. explain why robots are popular in JapanB. tell people that robots can work as waiters in restaurantsC. persuade readers to come to restaurants that use robotsD. show the similarities between robots in 1970 and new robots