PM 2.5是指大气中直径小于或等于2.5微米的颗粒物，也称为可入肺颗粒物．被吸入人体后会直接进入支气管，干扰肺部的气体交换，引发包括哮喘、支气管炎和心血管病等方面的疾病．PM2.5检测可推动环境质量提升．下列能源在利用时对大气环境污染最大的是（　　）

世界上使用最广泛的语言是汉语。

如图，水平地面上盛水柱形容器A，内有质量为400g、体积为10³cm³的正方体物块B，通过一根10cm的细线与容器底部相连，此时水面距容器底30cm.下列说法正确的是(ρ水=1.0×10³kg／m³)：（   ）

    When I was young, my father had one of the first telephones in our neighborhood. I remember the shiny box on the wall. But I was too little to reach it. I could only listen to my mother talk on it.

    I discovered that inside the-wonderful box lived an amazing person whose name was Information Please. There was nothing she did not know.

    One day my mother went out. I accidentally hurt my finger when I was playing with a hammer. I walked around the house sucking my finger, finally seeing the telephone. Quickly I dragged a chair over and climbed up.

    “Information Please, ”I spoke into the receiver. A click or two and a small clear voice spoke into my ear. “Information.”

    “I hurt my finger…”I cried into the phone.

    “Isn't your mother home?” came the question.

    “Nobody's home but me.” I sobbed.

    “Are you bleeding?” the voice asked.

    “No,” I replied, “I hit my finger with the hammer and it hurts.”

    “Can you open your icebox?” she asked. I said I could.

    “Then take a little piece of ice and hold it to your finger.” said the voice.

    After that, I called “Information Please” for everything. I asked her for help with my geography and she told me where Philadelphia was. She helped me with my math. She told me her name was Sally.

    Then, there was the time my pet canary（金丝雀）died. I called “Information Please” and told Sally the sad story. “Why is it that birds sing so beautifully and bring joy to all families, only to end up as a pile of feathers?” She listened, then said quietly, “Paul, always remember that there are other worlds to sing in.” Somehow, I felt better.

    One day when I called “Information Please” again, a different voice answered “Information.”

    I asked for Sally. “Are you a friend?” she said.

    “Yes,” I answered.

    “I'm sorry to have to tell you this,” she said. “She died five days ago.” Before I could hang up she said, “Wait a minute. Did you say your name was Paul?”

    “Yes.”

    “Well, Sally left a message for you. The note said, ‘Tell him I still say there are other worlds to sing in. He'll know what I mean.'” I thanked her and hung up. I knew what Sally meant.

阅读以下短文，回答下列小题。

菊花

      ①菊花原产地是中国。菊花又名鞠，还有黄花、九华、金蕊、金精、帝王花等三四十个称谓。菊花大多开放在秋寒之季，飒飒冷风中，百花凋落，唯有菊花灿然绽放，让人心生敬意。

      ②菊花分类的标准多种多样。依花径可将菊花分为大菊和小菊；依花期可分为春菊、夏菊、秋菊、冬菊（寒菊）和四季菊；依花色可分为黄、白、粉、紫、橙、褐、绿以及间色和复色等。在人们的传统印象中，菊花都是黄色的。这实际上是一种错误认识。

      ③菊花的适应性强。它喜爱阳光也耐寒冷。光照充足的地方，菊花长得更健康、更茁壮，而在少光、寒冷的地方菊花也能生长。与郁金香等花卉相比，菊花对土壤的要求不高。它更适宜生长在排水良好的土壤中，但潮湿的环境中也能寻觅到它的芳容。播种或扦插的方式菊花都可成活。菊花良好的适应性，使其在中国自华南至东北地区均能栽植。菊花是很多城市绿化的首选花卉。

      ④菊花具有极高的观赏价值。菊花端庄素雅，晚香凝秀，花姿飘逸，淡意疏容，是著名的观赏植物。“重阳日赏菊”始于晋代陶渊明，现在已成为我国的一种文化传统。秋季，我国许多城市常常举办规模不等的“菊展”供市民欣赏。

      ⑤菊花具有一定的药用价值。菊花作为药材使用，距今已有2200多年的历史。中医学认为菊花具有散风清热、平肝明目的功效。它的这一功效，历来为广大民众所认可。例如，有人经常饮用菊花茶，就是为了达到明目润咽的目的。

      ⑥菊花自古受人喜爱，国人爱其质朴的形象更爱其高洁的品格。菊花是中国的传统名花之一，后来也风靡世界，是中国送给世界的一份美丽礼物。

                                                                                                                                                                （选文有改动）