题干

过滤后的食盐水仍含有可溶性的CaCl2、MgCl2、Na2SO4等杂质,通过如下几个实验步骤,可制得纯净的食盐水:正确的操作顺序是(   )

①加入稍过量的Na2CO3溶液;

②加入稍过量的NaOH溶液;

③加入稍过量的BaCl2溶液;

④滴入稀盐酸至无气泡产生;

⑤过滤.

A:③②①⑤④

B:①②③⑤④

C:②③①④⑤

D:③⑤②①④

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A

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Dear Mr. Smith,

    I am seeking an opportunity to work with World Destiny as a Computer Systems Manage. My professional experience and my awareness of your high reputation and great achievements have led me to want to work for World Destiny.

    Since 1998 I have focused on computer-system design and training. As Systems Administrator for Newport Museum for the past two years, I have directed accounting, capital campaign and publication production. We designed the system from scratch, developing all applications, policies, procedures, and training programs. I was well prepared for such a challenge by my previous positions as a Systems Support Specialist and MicroComputer Assistant for the Imperial Corporation of America.

    Over the years, I have worked with Novell, using programs including dBase, Wordstarand Microsoft Word. This familiarity with a variety of hardware and software has helped me to get up to speed on nearly any computer with a minimum training period.

    Additional experience in other fields also adds my value to World Destiny. As a Market Research Coordinator for Cushman & Wakefield of California, I not only researched and maintained(维护)a comprehensive database of Silicon Valley, but also produced statistical and written reports that support Cushman & Wakefield' reputation. Previously, I organized companywide annual sales meetings for Qualogy, Inc.

    Mr. Smith, while this experience more than qualifies me to join any number of successful companies, it is my personal goals that lead to my interest in being part of the World Destiny team. I believe my computer, promotional, and organizational skills, fueled by my beliefs, make World Destiny and me right for each other. Can we arrange an interview at your earliest convenience? I will call within the next week to arrange a meeting.

Sincerely,

Beth Henning