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Q、R、X、Y、Z是短周期元素,原子序数依次增大.Q的基态原子最外层s轨道和p轨道电子数相等;R的一种氢化物是常见的碱性气体;X在同周期元素中,其氧化物的水化物是最强的碱;Y的一种氧化物能使品红溶液褪色;Z的最高价氧化物的水化物是最强的酸.

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How Women Were Freed From Their Homes

    As late as 1800, a woman's only place was in her home. Women in business were unheard of. No respectable woman would dream of entering what was strictly a “man's world”. Even if she would, what could she do? Men were sure that no woman could do a job well outside her home.  This was a widely-accepted idea. When the famous Bronte sisters began writing books in 1846, they had to resort to using men's names as aliases.

    Teaching was the first profession opened to women, soon after 1800. But even that was not easy for women to take because most high schools and colleges were open only to men. Oberlin College in Ohio was the first college in America to take in women.

    Nursing was regarded as a respectable profession for women only after Florence Nightingale won high credit for her nursing career and became famous. Miss Nightingale opened the first training school for nursing in 1860 in England.

    The invention of typewriters in 1867 helped to bring women out of their homes to join the business world. Because women are careful and have nimble fingers, businessmen found that they were well suited to this kind of work.

    By 1890, tens of thousands of women were working in schools, hospitals, shops, offices, and factories both in England and the States. Some even managed to become doctors or lawyers. The idea of women working in business and other circles was accepted.