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1.直线l//m,A、B为直线l上两定点,线段CD在直线m上运动时,四边形ABCD的面积是?2.等腰梯形的上底与高相等,下底是高的3倍,则底角为多少度?3.正方形的边长是5cm,以它的对角线为边长的等边三角形 初二的3道数学题1、若数X的平方根为3A+1和A-2，求原数X2、设2+根7的小数部分为A，求A（A+4）的值3、已知X=Y+3倍的根3，求X²+X+Y²-2XY-Y的值 欧洲气候分布图 急 求中国及世界气候类型分布图 非洲气候类型分布图0°15°E所在地是什么气候?索马里地区是什么气候? 求世界气候类型分布地图! 英语翻译A candy assortment consists of seven flavors of chocolate-covered creams packed in two-layered boxes with 27 creams in each layer.The flavors are always packed in rows so that the flavors varies with each piece in the following order:vani 342,198,75If the digit 2 in the number above is replaced by the digit 6,by how much will the number increase?In how many different ways can three men and three women be arranger in a line so that the men and the women alternate? 自古以来台湾咋么是中国的领地,西藏?For example：从三国时期吴国大将weiwen到达台湾.要连考了! Sat数学题求解释和过程At a department store,3/5of the items are discounted by 50 percent, 1/5of the items are discounted by 70 percent, 1/10 of the items are discounted by 80 percent, and all other items are not discounted. If one item is to 为什么说新疆、西藏、台湾自古以来是我国的领土简要一点,不要漏了任何一个史实, 英语翻译If 3 times 1 less than a number n is the same as twice the number increased by 14,what is (A) 15 (B) 17 (C) 19 (D) 21 (E) 23 为什么说“西藏”“台湾”“新疆”自古就是中国的领土? If "p" is a prime number,how many factors does "pn"have?抱歉，我没有看懂你的解释。 英语翻译A bag contains 6 chips,numbered 1 through 6,If 2 chips are chosen at random without replacement and the values on those 2 chips are multiplied,what is the probability that this product will be greater than 20?（A）1/30 （B）1/15 (C)2/ 某日,上海受台风影响,其风向为西北风,则此时台风中心大致位于上海的A． 东部 B．西部 C．南部 D．北部 某日,上海受台风影响,其风向为西北风,则此时台风中心大致位于上海的 A． 东部 B．西部 C．南部 D．北部 高一地理 上海受台风影响,风向为西北风.台风中心位于上海的?如题.麻烦解释一下.谢谢.上海受台风影响,风向为西北风.台风中心位于上海的?= =只有东、西、南、北 四个选项... sat数学题求助 SAT的数学题In an election 2.8 million votes were cast and each vote was for either A(人名） or B （人名） A received 28000 more votes than B.what % of the 2.8 million vtes were cast for 太久没做这样的题了.都忘了.如何解决这 北京春季出现沙尘天气的时候,以什么风向为主?说出判断的依据,要减轻沙尘天气对北京的影响,应采取哪些措 北京春季出现沙尘天气的时候,以什么风向为主.要非常具体的哪一种.50字. 如何减轻沙尘天气对北京的影响? 1.沙尘暴是只在春天才发生吗?2.北京沙尘暴的沙源在哪?3.为什么春天会有沙尘暴? 北京沙尘暴以什么风向为主?如题 SAT 数学题求解答On a number line, three points have coordianates r, s, and t, where r＜s＜t, which of the following cannot be true? A)tr+s C) t=r+s D) s=(r+t)/2 E)t=(r+s )/2 上海的夏季主导风向是什么因为建筑物最好和夏季主导风向垂直 我国各地的主导风向是什么?例如：上海：主导风向：冬季多北风、夏季多东南风,最大风速10级 上海主风向请问上海的全年主要风向是什么风?我也这样想，但是老师说是东北风，我很困惑。 上海风向上海那个季节刮什么风,最好是详细资料,多一点,权威的. SAT数学题求翻译及完整解题步骤A rectangular tabletop consists of a piece of laminated wood bordered by a thin metal strip along its four edges. The surface area of the tabletop is x square feet, and the total length of the strip before it 英语翻译The total daily cost c,in dollars,of producing x units of a certain product is given by the function c(x)=k/5,where k is a constant (4x+1200)/x.If 20 units were produced yesterday for a total cost of $640,what is the value of 答案是50,