为了解某小区“全民健身”活动的开展情况，某志愿者对居住在该小区的50名成年人一周的体育锻炼时间进行了统计，并绘制成如图所示的条形统计图，这组数据的众数和中位数分别是（　　）

看图，阅读短文，判断正误。

    Tommy is a boy. He is short and thin. He is 10 this year.

    Sally is his sister. She is 11. They go to school together.

    Tommy often gets up(起床) at 6:30 in the morning. He likes sunny days, He doesn't like rainy days.

    Tommy loves his mum. When he leaves(离开) home, he always says "Goodbye!" to her.

I want to go to the library ____（and/but） it is ten to seven.

读某地近地面气压带、风带示意图，回答下列问题。

我国历史上第一个统一的多民族的中央集权的国家是____ 朝。