An old woman asked me what was ____ (miss).

    Tomorrow is Sunday . Sally will go to the park 1her best friend , Amy . The bus stop is 2her home .So Sally will 3to the bus stop and take the No.2 bus 4 Amy's home ;5they will go to the park on 6，7the park is near Amy's home .They will play chess 8the tree. They will 9 pictures and watch the beautiful flowers ,10

下列关于氧气的说法中错误的是

一束光与水面成38°角入射，其反射光线与折射垂直．则反射角是　 ____，折射角是 ____

在自然界中存在着氧的循环系统，其中能将二氧化碳转化为氧气的是(  )