题干

如图,在平面直角坐标系中,二次函数y=(x-a)(x-3)的图像与x轴交于点A、B(点A在点B的左侧),与y轴交于点D,过其顶点C作直线CP⊥x轴,垂足为点P,连接AD、BC.


上一题 下一题 0.0难度 选择题 更新时间:2020-02-07 05:24:28

答案(点此获取答案解析)

同类题3

阅读下文,回答相关问题。

                                                                                                                                        乐山大佛
        ①在四川乐山的三江合口处,坐着一尊受香火的清廉大佛。
        ②他叫弥勒,弥勒佛。但不是那位袒露大肚皮的弥勒佛,那位成天笑眯眯的“老好人”——“大肚能容天下难容之事,慈颜常笑世上可笑之事”的弥勒佛。
        ③他是一位严肃的沉思者,面色温和,神情严肃。他不是什么都笑——世上并没有那么多可笑的事,也不是什么都容——天下一切丑恶都容。
        ④他的严肃的思考,首先来自缔造他的海空和尚。一千一百多年前,凌云寺和尚海空为了减缓三江合口后的凶猛水势,避免沉舟淹死众生,倡导在峭崖临江边造就一座佛。他光头顶烈日,下雪披袈裟,四处化缘,钱化得不少了,但当地官吏要冻结:“如果你真心造佛,就把眼珠挖出来见我。”
        ⑤大佛兴建了,海空的眼珠也没有了。海空的眼珠是为建大佛而失去的。世上除了生命,还有比眼珠更珍贵的东西吗?
        ⑥由于意识到自己的职责,因此,乐山乐水佛不乐。他坚守岗位,从不擅离职守,从不懈怠松驰,从不向惊涛恶浪屈服。他成了实现海空和尚遗愿,拯救三江芸芸众生的中流砥柱。

        ⑦他常常想起塑造他的工匠们。是的,他是伟大的:头与山齐,脚踩江水,身高71米,比阿富汗世界第一大佛还高18米,可称世界第一伟佛了。如果不是设计、雕塑他的工匠们经过九十年的千刀万凿,他仍然是半片石头山,普普通通通到处可见谁也不会瞄一眼的石头山。为了他的降生,有多少人摔下峭壁,跌进的江心,付出了生命!他是真正的人民之子。
        ⑧他永远不忘这最根本的一点,因此他从不居功,从不索取,从不接受人民的香火和祭祀。在这里,看不到一柱香火,一支红烛,一从跪拜,看到的只是他伟岸的身躯,两袖清风,一尘不染。为了根绝香火,他一开始就釜底抽薪铲除了滋生这些东西的土壤:立脚点在临江的悬崖上,没有地方让人设立祭祀他的殿堂,周围全是香火插不进的岩体,连他的脚趾甲也是向下倾斜的,人站上去就会跌倒,所以连下跪朝拜也没有地方。
        ⑨人们只能簇拥在轮渡上才能看到他那顶天立地的尊容并默默遥致祈祷。
        ⑩有人感叹,有人惊奇,有人礼赞:“呀,连小小的土地庙都有几柱香火哩,而他——世界第一大佛,连一柱香火也没有。

同类题5

阅读理解

    A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度) of yellow makes it less difficult for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.

    The study was led by Prof Ho. To test whether there was a relationship between the color of a taxi and the number of accidents the taxi had, the research team analysed data collected by the largest taxi company in Singapore. The researchers found that yellow taxis have about 6. 1 fewer accidents per 1,000 taxis per month.

    They also studied the economic effect of changing the color of the entire fleet of taxis to yellow. The Singapore taxi company involved in the study owns about 16,700 taxis in a ratio (比例) of one yellow to three blue taxis. If a commercial decision is made to switch from blue to yellow taxis, 76. 6 fewer accidents will occur per month or 917 fewer accidents per year.

    Assuming an average repair cost of $1,000 per car and a downtime of six days, the color of all taxis to yellow could produce an annual saving of $2 million.

    “We are eager to continue to validate (证实) the findings of our study by looking at the use of yellow in other types of public transport, such as school buses. For example, we hope to compare the accident rates of yellow school buses against those of other colors to find out if yellow is indeed a safer color for school buses. Besides, we' re also interested to look at private-hire vehicles and do a comparison of the accident rates of vehicles that are of different colors explained Prof Ho.

根据短文内容,选择最佳答案,并将选定答案的字母标号填在题前括号内。