金黄色葡萄球菌是人类化脓感染中最常见的病原菌，可引起食物中毒、肺炎、肠炎等．某研究小组的同学用所学的微生物的实验室培养的方法进行“变质牛奶中金黄色葡萄球菌的分离和计数实验”，部分实验处理和结果如下图．（注：培养皿旁的数字代表菌落数目；实验室条件满足金黄色葡萄球菌的生长、繁殖；实验操作规范；实验过程严格做好各项防护防扩散等工作）请回答相关问题．

阅读下列短文，从每题所给的四个选项（A、B、C和D）中选出最佳选项。
   Bored with your life? Dreaming of something different? When I feel like that I look up and wonder what life would be like 400km above my head. That's where the International Space Station orbits the Earth, with six astronauts living and working on board, for months at a time.
How do they sleep? They spend the night floating in a sleeping bag inside a small cubicle on the ceiling. American astronaut Sunita Williams explains: "It's like a little phone booth but it's pretty comfy and it doesn't matter if I turn over and sleep upside down. I don't have any sensation in my head that tells me I'm upside down."
Brushing your teeth in a place where you can't have a tap or a sink can be a challenge. Can you imagine the mess that running water would make in zero gravity? Canadian astronaut Chris Hadfield uses a straw to put a big blob of water from a sealed bag onto an ordinary toothbrush and adds a little toothpaste - which he has to swallow when he's done.
Daily exercise is essential. The lack of gravity makes bones more brittle and muscles lose strength – so astronauts are encouraged to work out for at least two hours a day.
The role of astronauts in the International Space Station is to act as lab technicians for scientists back on Earth. So they spend their time maintaining their environment and performing and monitoring experiments in a confined space about the size of a Boeing 747. Almost every task is carefully planned by mission control - although most astronauts spend their first days losing stuff until they get used to sticking everything they use to the walls with Velcro, duct tape or clips.
One of their most valued perks is the view from "the office", dominated by that gigantic blue ball down there, sitting in the darkness of space. Wow! Absolutely breathtaking!

某有限责任公司，注册资金80万，其中股东A出资40万，股东B、C各出资20万。公司因经营不善一年后负债150万，而资产只有50万。资不抵债申请破产，则该公司和股东A、B、C分别承担的责任是（   ）

阅读《“煤改气”与燃气蒸汽锅炉》，回答问题．

“煤改气”与燃气蒸汽锅炉

当前，大量散烧煤消费是造成雾霾的主要因素之一．数据显示，我国直接燃烧煤炭产生的二氧化硫占全国总量的86%，产生的PM2.5占总量的50%以上，把工业锅炉、居民取暖等用煤改为用电或气，可以大幅减少直燃煤，极大改善空气质量．

针对燃煤取暖对空气污染的贡献率高（我市约为22.4%）这一问题，北京市启动了农村地区“煤改电”“煤改气”工程，即用清洁能源替代燃煤．北京市“煤改气”工程使用天然气作为气源，因为天然气的热值为3.8×10⁷J/m³，远高于人工煤气的热值1.5×10⁷J/m³．

如图所示的燃气蒸汽锅炉，是用天然气、液化气、人工煤气等气体作燃料在锅炉中燃烧，燃烧后的高温烟气通过烟气导管在水套内、外、中管里盘绕，最终经烟囱排出炉外．此过程中气体燃料燃烧释放出来的能量不断传递给水套中的水，使其温度升高并产生带压蒸汽形成热动力．

燃气蒸汽锅炉是整个水暖系统的核心，那么，它就不得不对水暖的能耗问题承担主要责任．让我们看一下藏在锅炉背后的秘密：锅炉“热效率”．

所有生产燃气锅炉的厂家均声称其“锅炉热效率达到了90%以上”．那么，我们是不是应该认为：天然气在锅炉中燃烧释放的能量至少有90%都被水吸收了呢？错！锅炉“热效率”是指锅炉将煤气、天然气等转换成热能的能力，也就是锅炉内燃料充分燃烧的能力，即燃烧在锅炉中燃烧放出的热量与等质量的燃料完全燃烧时放出的热量之比．至于水在锅炉中被加热吸收的热量与锅炉内燃料燃烧放出热量的比，可以用“热交换率”来描述，与锅炉“热效率”的含义不同．

燃气锅炉烟囱口的废气温度越高说明该锅炉的“热交换率”越低，大量的热能没有被水吸收而随着烟气被白白地排到了室外空气中了．经实地测试，某知名品牌燃气锅炉烟囱出风口的温度为120℃，而绝大多数家用燃气锅炉烟囱的出风口温度都在160℃以上，有的甚至达到了200℃．那么降低燃气锅炉烟囱的出风口温度将是提高锅炉“热交换率”的有效途径．

请根据上述材料，回答下列问题：

如图，将一副直角三角板叠在一起，使直角顶点重合于点O，则∠AOB+∠DOC=____度．