python3运算符优先级

Hello,my Chinese friends,I'm Bush,former president of USA,I'm glad to be here. 请根据对联的相关知识,以节约用水为内容完成下面这幅对 生态和谐决定国家振兴请根据对联的相关知识,以节约用水为内容完成下面这幅对联上联：下联：生态和谐决定国家振兴 圆的相关知识如图 如何计算太阳高度角和相关知识? 袋式除尘器除尘效率怎么样检测的? 1.I v___ my grandmother with my mother yesrerday.2.The musician w___ a new song last month.3.We go to school five days a w___.4.How did you s___ your last Sunday?5.I am a m___ school student. 如何用量筒测量固体体积急 He had a ten days visit to Canada last month.纠正语法错误说明缘由知识点. he had a（）visit to canada last mouth A、ten days B、ten-day C、ten-days D、ten day1、我认为ab两个答案都对,其实正确答案是b.我想知道a为什么不选.2、还有这个是过去时因为有last month为什么visit不用visited 为什么可以用盐酸来除去热水瓶中的水垢=.= 求有关反应的化学方程式来说明除去的水垢的原理 mr.wang work____only ten days last month 热水瓶中的水垢用稀盐酸除去行吗?虽然HCl能除去CaCO3,Mg(OH)2,但HCl会与内胆上的银反应生成氯化银沉淀,这怎么办?虽然理论上Ag与稀盐酸不会反应，但实际中总会有意外，比如说银已经变成某化 用盐酸去除水垢的原理?用适量盐酸能去除热水瓶胆壁上的水垢（主要成分是Mg(OH)2和CaCO3）说明原理,并写出有关方程式 The Niagara Falls___great fame in the world.A.enjoy B.enjoys C.is D.are我觉得主语是专有名词应该在B和C中选,所以答案是不是错了.还有为什么这儿不能选BE动词呢? The water flows into the Niagara River and over the falls on its way to the sea.over the falls I visited the museum last week(改为否定句) (be) you happy after you visited the museum last week 英语翻译要准确的. I'm glad ___ a visit to him last week? A.to pay B.to have paid IS THIS factory to which you paid a visit last week句中的 to which可不可以换成 that? 请问这是什么颜色的?什么染料配出来的 求一环境生态学论文 染料强度400%是什么意思,是不是代表上染率会高?所有颜色染料都能达到400%吗? 环境生态学的发展趋势是什么? 根据例句改下句子 比如 l went to (the farm) last week 改 Where did you go last week?1.They (wentto the beach) on vacation 2.My father stayed (at home) last Sunday 3.The people in the shop were (friendly) 4.Bill went to the park (by bus) 5.P Did you went to Binjing last week? Last month my Mom left------ a few days.横线上填哪个介词呢? 英语翻译 My Only Wish (This Year) 歌词 在3支试管中分别盛有浓硫酸、稀硝酸、稀盐酸,试设计简单的实验方案鉴别他们,写出有关反应的化学方程式不是浓硫酸是稀硫酸 高二化学三支试管中分别盛有稀硝酸稀硫酸稀盐酸怎样用实验方法鉴别 写一篇与环境生态学有关的论文,都可以写哪些方面的问题呢?可以写什么内容呢?