Question

帮忙翻译一下了，谢谢

美国首都华盛顿，全称“华盛顿哥伦比亚特区” (Washington D.C.) ，是为纪念美国开国元勋乔治•华盛顿和发现美洲新大陆的哥伦布而命名的。华盛顿在行政上由联邦政府直辖，不属于任何一个州。是美国文化、教育中心之一。位于马里兰州与弗吉尼亚州之间。
范围与哥伦比亚特区相同，市区面积174平方公里，人口57．8万(1993)，其中黑人约占70％；标准都市统计区还包括马里兰的2个县、弗吉尼亚的4个县及费尔法克斯、福尔斯彻奇、亚历山德里亚3个城镇，人口320万；市区位于波托马克河和阿纳卡斯蒂亚河汇合处的东北岸“地势平坦，平均海拔约22米，仅西北角有和缓的起伏高地；气候冬冷，夏热，全年湿润；年平均气温12．6℃，7月20-31℃，1月3--6℃；年平均降水量1068毫米，季节分配较均匀。
华盛顿原是一片灌木丛生之地，只有一些村舍散落其间。1789年，美国联邦政府正式成立，乔治•华盛顿当选为首任总统。当国会在纽约召开第一次会议时，建都选址问题引起激烈争吵，南北两方的议员都想把首都设在本方境内。国会最后达成妥协，由总统华盛顿选定南北方的天然分界线——波托马克河畔长宽各为16公里的地区作为首都地址（1790年）。城市规划为巴罗克建筑与凡尔赛、巴黎的建筑形式相结合，以国会大厦、白宫等建筑物为中心修建林荫大道向四方辐射，再于其间增筑格状街道，是由法国工程师皮埃尔•夏尔•朗方总体规划和设计。新都尚未建成，华盛顿便于1799年去世。为了纪念他，这座新都在翌年建成时被命名为华盛顿。
拉斯维加斯气候
拉斯维加斯地处美国内华达沙漠边陲，周围环绕著1000米至3000米的高山。拉斯维加斯的气候四季分明。夏季是典型的沙漠性气候，正午的温度常常高达38゜左右，而晚间的温度相对凉爽。常常会有雷阵雨天气，温度要超出平均水准。冬季整体上是气候温和适宜，白天的平均温度在15゜左右。尽管偶尔会出现非常高温天气，但是春季和夏季仍然是最宜人的季节。拉斯维加斯很少受到恶劣气候的袭击，并且是全国所有的大城市中相对湿度最低的区域之一。 周围都是沙漠，和死亡谷一样干燥。因为少雨的缘故，空气会较为干燥，最好准备一点保湿用品。
拉斯维加斯的时间比北京慢16小时。

Answer 1

Washington, the name "Washington, DC" (D. Washington), to commemorate the American founding fathers George Washington and Christopher Columbus discovered the New World and American names. Washington by the federal government directly under the administration, does not belong to any one state. Is American culture, education centers. In Maryland and Virginia between.
The scope of Columbia and the same urban area of 174 sq km, population 578,000 (1993), which accounts for about 70% black; Standard city statistical area also includes two Maryland counties, the four counties of Virginia and Fairfax, Falls Admiral Church, Alexandria Hill Alexandria three towns, population 3.2 million; in urban Agence Presse Potomac River and the confluence of River coast, "however, the average elevation of about 22 m, with only moderate fluctuations northwestern highlands; climate winter cold, summer heat, humid year; the average temperature of 12.6 ℃, July 20-31 ° C, Jan. 3 - 6 ℃; the average 1068 mm of precipitation, seasonal distribution is uniform.
Washington was originally one of the bush, only a few cottages scattered meantime. In 1789, the United States formally established the federal government, led by George Washington was elected president. When Congress convened in New York at the first meeting, a capital site has aroused heated arguments, both the south and north side of Members want to set up in this capital of the territory. Congress finally reached a compromise, Washington selected by the President of the South and the North of natural dividing line - Potomac River for 16 square kilometers of the capital as the address (1790). Urban planning for Baroque architecture and Versailles, Paris architectural forms combine to Capitol, the White House and the construction of buildings for the Center Boulevard to the Quartet radiation, in the meantime by further build trellis streets by the French engineer Pierre Charles • • Lang, overall planning and design. Xindu not yet completed, Washington in 1799 to facilitate death. To commemorate him, this new capital was built in 1992 and named Washington.
Las Vegas climate
Located in Las Vegas, Nevada desert border, surrounded by 1,000 meters to 3,000 meters mountain. Las Vegas climate four distinct seasons. Summer is a typical desert climate, the temperature often noon Provisional up 38%, while the night-time temperature relatively cool. Often there thunderstorm weather, the average temperature exceeded the standard. Overall, the winter climate is mild appropriate, the average daytime temperature of 15 Provisional around. Although occasionally a very hot weather, but spring and summer is still the most pleasant season. Las Vegas is rarely bad weather attacks, and is all of the country's major cities in the minimum relative humidity of the region. Surrounded by desert, and as Death Valley dry. Because drier because of the dry air, the best preparations for the 1:00 moisture supplies.
Las Vegas Beijing slower time than 16 hours.

Answer 2

174 sq km, elected president. When Congress convened in New York at the first meeting, a capital site has aroused heated arguments, both the south and north side of Members want to set up in this capital of the territory. Congress finally reached a compromise, Washington selected by the President of the South and the North of natural dividing line - Potomac River for 16 square kilometers of the capital as the address (1790). Urban planning for Baroque architecture and Versailles, Paris architectural forms combine to Capitol, the White House and the construction of buildings for the Center Boulevard to the Quartet radiation, in the meantime by further build trellis streets by the French engineer Pierre Charles • • Lang, overall planning and design. Xindu not yet completed, Washington in 1799 to facilitate death. To commemorate him, this new capital was built in 1992 and named Washington.
Las Vegas climate
Located in Las Vegas, Nevada desert border, surrounded by 1,000 meters to 3,000 meters mountain. Las Vegas climate four distinct seasons. Summer is a typical desert climate, the temperature often noon Provisional up 38%, while the night-time temperature relatively cool. Often there thunderstorm weather, the average temperature exceeded the standard. Overall, the winter climate is mild appropriate, the average daytime temperature of 15 Provisional around. Although occasionally a very hot weather, but spring and summer is still the most pleasant season. Las Vegas is rarely bad weather attacks, and is all of the country's major cities in the minimum relative humidity of the region. Surrounded by desert, and as Death Valley dry. Because drier because of the dry air, the best preparations for the 1:00 moisture supplies.
Las slower time than 16 hours.

Answer 3

你可以上些介绍美国的英文网站，在概况中可以找到类似的表达。