已知下列命题：①若a﹥b则a＋b﹥0；②若a≠b则a²≠b²；③角的平分线上的点到角两边的距离相等；④平行四边形的对角线互相平分。其中原命题和逆命题都正确的个数是（    ）

    Chicago is becoming one of the country's most wonderful cities to film television. When this wonderful place is properly represented in a film, I cannot help but love it! Here are some movies that feature this great city.

    Southside With You

    Neighborhood: The whole South Side

    Director: Richard Tanne

    Starring: Tika Sumpter and Parker Sawyers

    Rotten Tomatoes Score: 92%

    Released: 2016

    Genre（类型）: Biography, Drama, History and Romance

    High Fidelity

    Neighborhood: Wicker Park

    Director: Stephen Frears

    Starring: John Cusack, Jack Black and Todd Louiso

    Rotten Tomatoes Score: 91%

    Released: 2000

    Genre（类型）: Comedy, Drama, Music and Romance

    Mean Girls

    Neighborhood: This one is famous since it takes place in Evanston and some other parts of the North Shore.

    Director: Mark Waters

    Starring: Lindsay Lohan, Rachel McAdams and Amanda Seyfried

    Rotten Tomatoes Score: 83%

    Released: 2004

    Genre: Comedy

    Hoop Dreams

    Neighborhood: Cabrini-Green, West Garfield Park and Westchester, IL

    Director: Steve James

    Starring: William Gates and Arthur Agee

    Rotten Tomatoes Score: 98%

    Released: 1994

    Genre: Documentary, Drama and Sports

徐中约在《中国近代史：1600—2000，中国的奋斗》一书中写道：“他（指邓小平）把市场经济称作‘一种建立在公有制基础上的有计划的商品经济’，强调‘计划经济为主，市场经济为辅’，并要求做到两者的‘内部统一’。直到1992年，他才打破禁忌，公开宣称政府的中心任务就是建立‘社会主义的市场经济’。”材料中邓小平“打破禁忌”的论断(     )

基态Ni原子的外围电子排布式为____，该元素位于元素周期表中的第____族．