（1）请用化学符号填空：

①2个双氧水分子____ ；

②3个氢氧根离子____ ；

③标出BaO中Ba元素的化合价____ ；

（2）如图表示在一定条件下，物质转化过程的围观示意图，请根据图形信息回答问题：

①CO分子中C、O元素的质量比为____ ；

②O^2﹣核外电子数为____ ；

③该过程的化学反应方程式为____

根据短文内容，判断正(T)误(F)。
   My name is Bill. I get up at twenty to seven in the morning. Then I have breakfast. After breakfast I go to school. We have four classes in the morning. I have lunch at school, but on Sundays I have lunch at home with my family. I often have supper at home. I often help my mother cook. My mother is an English teacher, and she often helps me with my English.

如图，以10m/s的水平速度抛出的物体，飞行一段时间后垂直撞在倾角为θ=30°的斜面上，空气阻力不计，则物体飞行的时间为（   ）