因表面粗糙使超声波束产生的漫射称为（）。

[单选题]Passage 2Old stereotypes die hard.Picture a video-game player and you will likely imagine a teenage  boy, by himself, compulsively hammering away at a game involving rayguns and aliens that splatter when blasted. Ten years ago that might have borne some relation to reality. But today a gamer is as likely to be a middle-aged commuter playing "Angry Birds"on her smartphone. In America, the biggest market, the average game-player is 37 years old. Two-fifths are female Over the past ten years the video-game industry has grown from a small business to a huge, mainstream one. With global sales of S56 billon in 2010, it is more than twice the size of the recorded-music industry. Despite the downturn, it is growing by almost 9% a year.Is this success due to luck or skill? The answer maters, because the rest of the entertainment industry has tended to treat gaming as being a lucky beneficiary of broader technological changes. Video gaming, unlike music, film or television, had the luck to be born digital. In fact, there is plenty for old media to learn.Video games have certainly been swept along by two forces: demography and technology. The first gaming generation the children of the 1970s and early 1980s-is now over 30. Many sill love gaming, and can afford to spend far more on it now. Meanwhile rapid improvements in computing power have allowed game designers to offer experiences that are now often more cinematic than the cinema.But even granted this good fortune, the game-makers have been clever. They have reached out to new customers with new methods. They have branched out into education, corporate training and even warfare, and have embraced digital downloads and mobile devices with enthusiasm. Though big-budget games are still popular, much of the growth now comes from "casual"games that are simple, cheap and playable in short bursts on mobile phones or in web browsers.The industry has excelled in a particular area-pricing. In an era when people are disinclined to pay for content on the web, games publishers were quick to develop "freemium" models, where you rely on non-paying customers to build an audience and then extract cash only from a fanatical few.As gaming comes to be seen as just another medium, its tech-savvy approach could provide a welcome shot in the arm for existing media groups.What can you learn from“freemium”model？

[单选题]特斯拉把互联网的思维融入到了汽车制造里面去，把汽车做成了一个包含硬件、软件内容和服务的体验的工具，大大提升了消费者的一种体验效果。这体现了“互联网+”的（）。

[单选题]某病的流行曲线只有一个高峰，所有病例都集中在该病常见潜伏期这个时间段内，则可断定此暴发为（）

[判断题]在创业过程中，我们要明白由“因”到“果”的反馈是没有延迟的。

[单选题]如果一种商品的需求的价格弹性为1，价格由1元上升到1.04元会导致需求量（）

[单选题]“向上向外”操作法中如果承托乳房的手离开太早会导致（）

[单选题]“以美育代替宗教”这一主张是()美育思想的重要组成部分。

[单选题]内镜下取异物最严重的并发症是（）

[单选题]知识的本质是（），遵从唯一的真理，这个真理是不以人的意志为转移的”是有关知识定义的重要命题之二。

[单选题]种植乔木的分车绿带宽度不得小于（）m。

[单选题]因工件表面粗糙使超声波束产生的漫射叫（）

[单选题]因工件表面粗糙使超声波束产生的漫射叫做（）

[单选题]因表面粗糙使超声波束产生的漫射叫做（）。

[单选题]因表面粗糙使超声波束产生的漫射叫做（）。

[单选题]因表面粗糙使超声波束产生漫射叫做（）

[单选题]因表面粗糙使超声波束产生的漫射称为（）。

[单选题]因表面粗糙使超声波束产生的漫射称为（）。

[单选题]超声检测中，当表面比较粗糙时，宜选用（）。

[填空题]因物体表面粗糙而使超声波束产生的漫射叫做（）。

[单选题]因表面粗糙使超声波束产生漫射叫做（）