Helen is my friend. She is thirteen years old. She is ____ (study) in London, the capital city of England. She'd like to visit different ____ (place) and meet different ____ (people) when she is on holiday. She likes reading very much. Now, she's standing ____ (介词) line in a bookshop. She's buying ____ (冠词) English storybook.

(2015•山东）近年来，在我国与越南，新加坡、俄罗斯等国家的贸易中，使用人民币评价、结算的业务量不断上升，从2010年的0.51万亿元上升到2014 年的6.55万亿元。对外贸易中使用人民币计价、结算，有助于（   ）

计算：$\sqrt{32}-\sqrt{8}$=　2$\sqrt{2}$　；$\sqrt{12}\times \sqrt{3}$=____ ．