如果信用证未规定交单到期日的，银行不接受晚于装运日（）天后提交的单据。A、7天； B

（1）某同学按如图装置对质量守恒定律进行实验探究，反应前天平平衡，然后将稀盐酸倒入烧杯中与碳酸钠充分反应后，再称量，观察到反应后天平不平衡，天平指针向______偏转（填“左”或“右”）．该反应______质量守恒定律（填“遵守”或“不遵守”）．反应后天平不平衡的原因是______．

（2）由质量守恒定律可知，化学反应前后，一定不变的是______；（填序号）

①原子种类；②原子数目；③分子种类；④分子数目；⑤元素种类；⑥物质种类．

多指标安全综合评价的步骤包括？

Writing about music is like dancing about architecture, or so the saying goes. Sometimes attributed to Frank Zappa, other times to Elvis Costello, this quote is usually intended to convey the futility of such an endeavor, if not the complete silliness of even attempting it. But Glenn Kurtz’s graceful memoir, Practicing: A Musician’s Return to Music, turns the expression on its head, giving it a different meaning by creating a lovely, unique book.
Kurtz picked up the guitar as a kid in a music-loving family, attended the Long Island music school, and went on to play on Merv Griffin’s TV show before graduating from Tufts University. Motivating the young Kurtz was the dream of reinventing classical guitar, as if by his great ambition alone he could push it from the margins of popular interest to center stage-something not even accomplished by the late Spanish guitarist Andres Segovia, perhaps the only artist of the form ever to reach anything resembling widespread celebrity.
This book reads like a love story of sorts: Boy meets guitar. Boy loves guitar. Guitar breaks boy’s heart or, more precisely, the ordinariness of a working musician’s life does so. "I’d just imagined the artist’s life naively, childishly, with too much longing, too much poetry and innocence and purity," Kurtz writes. "The guitar had been the instrument of my dreams. Now the dream was over. "
Boy leaves guitar. Were the story to end here, this book would be a tragedy, but after nearly a decade the boy returns to guitar, and although he has lost the enthusiasm he had in his youth, he finds his love of the guitar again in a way he never could have appreciated before.
Although Kurtz is writing about a unique musical path, his journey speaks eloquently to the heart of anyone who has ever desperately yearned to achieve something and felt the sting of disappointment. "Everyone who gives up a serious childhood dream—of becoming an artist, a doctor, an engineer, an athlete—lives the rest of their life with a sense of loss, with nagging what it is," he writes. "Is that time and effort, that talent and ambition, truly wasted \

The book Practicing: A Musician’s Return to Music mainly tells that ______.

A．one will be made bitter by his frustration

B．reliving old dreams can be rewarding

C．without dreams life is incomplete

D．it’s inevitable for a musician to experience setbacks

车削加工的进给运动是：（）

A.刀具的旋转运动

B.刀具的横向或纵向移动

C.工件的旋转运动

在供应链竞争联盟战略中，厂家确定供应商的数量原则应该是( )。

A．独一供应原则

B．可替代原则

C．成本最低原则

D．长期可靠稳定原则