探索无限冷知识| 情侣之间出去旅游，应该注意些什么？ 冷知识分享平台

探索无限冷知识| 情侣之间出去旅游，应该注意些什么？ 冷知识分享平台

人能长生不老吗？？？

目前还无法实现长生不老的状态。人体的细胞和器官都有相应的寿命，无法永远维持完美状态。虽然科学技术在延长寿命方面有一定进展，但目前的研究仅能延缓衰老过程而非实现长生不老。

（通讯员 罗钰明）， 在防洪减灾工程方面，国家150重点项目——福建上白石水利枢纽工程可行性研究报告经水利部复审，离立项开工又近了一步；

17岁该找什么工作好了

17岁的人可以考虑以下几种工作： 1. 兼职：可以在学校附近或当地商铺找寻适合自己的兼职工作，比如服务员、收银员、送货员、文员等。 2. 家教：如果在某个学科有较好的成绩，可以考虑在周末或放学后当家教，辅导其他学生。 3. 实习：可以找一些与自己感兴趣的领域相关的实习机会，如博物馆、医院、科研机构等。 4. 社区志愿者：可以参与一些社区组织的志愿者活动，如托儿所、养老院、动物收容所等。 5. 网络兼职：可以在网络上寻找一些兼职工作，如网上销售、写作、翻译等。 总之，17岁时可以通过找兼职、实习、家教或志愿者等工作来积累经验、锻炼自己的能力和为未来打下基础。同时，要确保工作不会干扰正常的学业进程，做好时间分配。

方罐与扁圆罐的规格一般1L到5L，通常都是小口罐。，不得不说，他们在一起两年抱俩，也是速度够快的。

(1-1/2)+(1/2-1/3)+(1/3-1/4)+···+（1/2009-1/2010

To find the sum of the given series, we need to add all the terms together. (1 - 1/2) + (1/2 - 1/3) + (1/3 - 1/4) + ... + (1/2009 - 1/2010) We can simplify each term by finding the common denominator. 1 - 1/2 = 2/2 - 1/2 = 1/2 1/2 - 1/3 = 3/6 - 2/6 = 1/6 1/3 - 1/4 = 4/12 - 3/12 = 1/12 We can observe that each term follows this pattern - the denominator of the second fraction becomes the denominator of the first fraction in the next term. So, the series can be written as: 1/2 + 1/6 + 1/12 + ... + 1/2009 To find the sum of this series, we need to find the common denominator of all the fractions. The common denominator of 2, 6, 12, ..., 2009 will be the least common multiple (LCM) of these numbers. Calculating the LCM of these numbers is a bit lengthy. Instead, we can find the LCM of 2, 3, 4, ..., 2010, and then divide by the LCM of 2, 3, 4, ..., 2009. LCM(2, 3, 4, ..., 2010) / LCM(2, 3, 4, ..., 2009) = 2010 / 2 = 1005 So, the common denominator is 1005. To add the fractions, we need to express them with the common denominator: 1/2 = (1/2) * (1005/1005) = 1005/2010 1/6 = (1/6) * (1005/1005) = 167.5/2010 1/12 = (1/12) * (1005/1005) = 83.75/2010 Now we can add: 1005/2010 + 167.5/2010 + 83.75/2010 + ... + 1/2009 We can observe that the denominators of the fractions form an arithmetic sequence, and the numerators follow the same pattern. Using the formula for the sum of an arithmetic sequence: Sum = (first term + last term) * number of terms / 2 In this case, the first term is 1005/2010, the last term is 1/2009, and the number of terms is 2010. Sum = (1005/2010 + 1/2009) * 2010/2 Sum = (1005/2010 + 1/2009) * 1005 Sum = (1005 * 2009 + 1 * 2010) / 2 Sum = (2019955 + 2010) / 2 Sum = 2021965 / 2 Sum = 1010982.5 Therefore, the sum of the given series is 1010982.5.

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