单选题色彩饱和度是指( )。

单选题幼儿主动与外部环境相互作用的最重要的方式是()。

单选题下列人物中，既是诗人也是画家的是______。

单选题Among the throngs of Americans prowling the malls and trawling e-commerce sites, many are looking out for themselves. Retail-research firm NPD Croup said, thus far, about one third of consumers have engaged in what is called self-gifting. That's up from 12 percent in a typical pre-recession year, and up from the 19 percent who said they planned to do so last year. The Nationals Retail Federation, the dispenser of all holiday-related data, said in 2012, nearly 60 percent of shoppers would do so. The latest step in the evolution of our burgeoning culture of narcissism? Yes. Self-gifting makes psychological and economic sense given what Americans have endured these years. THE POST-BUST (破产) era has been a long, hard, heroic slog of balance-sheet improvement. Americans have labored to save money and hack away at the huge mountain of debt they accumulated during the credit boom. According to the New York Federal Reserve, consumers have knocked down their aggregate debt load from $12.67 trillion in the third quarter of 2008 to $11.31 trillion in the third quarter of 2012; credit-card debt is off $192 billion from the peak. Americans have cut their load by spending more carefully and engaging in that most un-American of traits: self-abnegation. After living frugally for so much of the year and for so many years who can blame a parent at an Apple Store for buying herself a new iPad? Indeed, self-gifting may actually be a function of the new abstemiousness. Let's say you've been holding off on replacing your old television. Why not buy it around November or December when insane promotions and free shipping are available? Besides, it's not like self-gifters are solely interested in self-pleasure. An NRF survey said that the typical self-gifter would spend about $140 on himself this year. For comparison's sake, the survey said the typical shopper would spent about $750 in all. After a long period of economic madness (remember the housing bubble and the dotcom mess), self-gifting is a sign of much-needed economic rationality. Shopping for others involves a certain amount of wrong guesswork with negative financial consequence. This year, for example, CEB Tower Croup claims that Americans will load $110 billion onto gift cards and give them as presents. But the market-research firm says that about 1.6 percent of that total, about $1.7 billion, will go used. Meanwhile, a large percentage of gifts wind up getting of people reported returning at least some of their gifts. Returns induce guilt and raise the specter of uncomfortable conversations about what happened to that giant striped sweater. But more significant, returns are bad for the environment. They lead to more trips to the mall, higher shipping costs, and the unnecessary use of packaging materials. These days, the rise of e-commerce means shopping is now antiseptic: sit and click. With the charm gone, we have to come up with other ways to make the experience pleasurable. As the song goes, "Have yourself a merry little Christmas".

单选题【2015年贵州丹寨】在新一轮的基础教育课程改革中，各学科的纲领性指导文件是()。

单选题某校经常组织同一学科教师相互观摩教学，课后针对教学过程展开研讨，提出完善教学的建议。这种做法体现的教师专业发展途径是()。

单选题农民：农具：土地相当于()。

单选题基因突变是指DNA分子中发生的碱基对的替换、增添和缺失而引起的基因结构改变，关于这种改变的说法正确的是( )。①若发生在配子形成过程中，将遵循孟德尔遗传规律传递给后代②若发生在体细胞中，一定不能遗传③若发生在人的体细胞中有可能发展为癌细胞④都是外来因素影响引起的

单选题#f小调的关系大调是______。 A.#A大调 B.D大调 C.bD大调 D.A大调

单选题儿童之间绝大多数的社会性交往是在()中发生的。

单选题第一次工业革命的标志是()。

单选题陈老师在讲“二氧化碳性质”时，讲台上放着两瓶没有标签的无色气体，其中一瓶是二氧化碳，一瓶是空气。怎么区分它们呢?陈老师边说边将燃烧的木条分别伸入两个集气瓶中，告诉学生使木条熄灭的是二氧化碳，使木条继续燃烧的是空气。这种教学方法是()。

单选题盛水的烧杯里有一只盛水的试管，加热烧杯使水沸腾。继续加热，保持烧杯中水始终沸腾。试管中的水能否沸腾?()

单选题依据《中华人民共和国教师法》，教师最基本的权利是()。

单选题Excel工作表中，第5行第31列的单元格地址可表示为()。

单选题幼儿园教育工作评价实行以______为主的制度。 A.其他教师评价 B.园长评价 C.家长评价 D.教师自评

单选题该石板属于()美术。

单选题教师执教义言文阅读课时指出《咏雪》与《陈太丘与友期》皆出自《世说新语》，以下该教师关于《世说新语》的介绍，表述有误的是( )。

单选题某版教科书《敬业与乐业》课后有一段补自，介绍了‘“因果类复旬”的特点。这段补白属于教科书的什么系统?（　　）

单选题著名芭蕾舞剧《天鹅湖》是______的作品。