小华外出旅游入住北京某酒店，看到服务总台的墙壁上有一排挂钟（如图）。她对造成不同时区时差的原因，解释正确的是（　　）

    It is the____of____today. My family are going to visit____. Uncle Li____my father. He is____for us at the airport. Now we are in the taxi to my relative's house. My brother is a____boy, so he is sitting between my mother and father. We are____very happy.

若${\left(2x+\sqrt{3}\right)}^4=a_0+a_{1}x+a_2{x}^2+a_3{x}^3+a_4{x}^4$，则${\left(a_0+a_2+a_4\right)}^2-{\left(a_1+a_3\right)}^2$的值为（    ）

宋初采取“田制不立、不抑兼并”的土地政策，到了宋真宗时期变成了“百姓康乐，户口蕃庶，田野日辟”的景象。这表明宋朝的土地政策（    ）