单项选择题 应征进口税税额在人民币50元（含50元）以下的，海关予以免征

多项选择题 以下属于产生未焊透和未熔合缺陷的因素有（     ）。A. 电弧热输入过大B. 焊接电流过小C. 焊接速度过高D. 电弧产生磁偏吹

未知题型 When Charles Darwin explained evolution (进化), the process he saw was natural selection (选择). It turns out human selection can also cause plants to evolvE.Take the case of the snow lot us, a rare (稀小的) plant that grows only high up in the Himalayas. Researchers have discovered that type of the plant has been becoming smaller over time—the one people like to pick.A type of snow lotus called Saussurea Laniceps is used in Tibetan and Chinese medicine and is increasingly demanded by tourists. The largest plants are picked, and that occurs during their only flowering perioD.The result is that only smaller, unpicked plants go to seeD.Selection caused by human beings is a powerful force, according to some scientists. They studied the plants picked over time and also compared the snow lotuses growing in heavily harvested areas with those found in places where people rarely picked them.They reported in an article that the heavily harvested snow lotuses have been getting shorter over the last century, while those in areas not picked have remained the samE.They found that in the heavily harvested areas, where only the smaller plants got to reproduce, the average height was 5.3 inches. The same plants in rarely harvested areas averaged 9 inches in height. And they noted that another type of snow lotuses which is not often picked, has not been changing.What does the word 'that'(Line2, ParA.3) refer to?A.Research done by Darwin.B.Seeds of Saussures Laniceps by natual selection.C.The picking of Saussures Laniceps by tourists.D.The Saussures Laniceps used in traditional Chinese medicinE.

单项选择题 掌握跨境电商行业的工作流程是合格客服应具备的技能

未知题型 The phrase 'to personalize each letter' (Line 1, ParA.3 ) means'______'.A.to print out each otherB.to personally send out each otherC.to find the address of each celebrityD.to make the letter suitable for a particular star

单项选择题 __________ honored as China's No. l Street, has become an all-weather pedestrian arcade. A、 Beijing North Road  B、Beijing East Road  C、 NanjingNorth Road  D、Nanjing East Road

单项选择题 跨境电商具有跨国交易、订单零碎的特点，因此在产品开发和采购、仓储等过程中容易出现混乱现象。

未知题型 What is Kelley's main purpose of writing the letters?A.To educate his students.B.To have pictures for his office wall.C.To improve his students' letter writing skills.D.To help his students know more about the celebrities.

单项选择题 会计主要的计量单位是实物。

单项选择题 根据履约模式不同可分为平台模式和自营模式。