如图，小颖利用一个锐角是30°的三角板测量一棵树的高度，已知她与树之间的水平距离为6m，AB为1.5m（即小颖的眼睛距离地面的高度），那么这棵树的高度为____ m．（结果保留根式）

根据短文内容及首字母提示，填写所缺单词，使短文意思完整，每空只填一词。
    Millions of American children attend summer camp. Traditional American summer camps offer young people a c____  to play many sports. These camps may be in the mountains. Or they may be in the woods, or at a lake. O____   camps teach activities like painting or music. Or t____ teach computer programming or foreign languages. Children at all kinds of camps m____  new friends. They learn new skills and develop independence (独立).
    Some children go to camp d____  the day and return home at night. These places are c____  day camps. Children as y____  as four years old attend day camps. Others stay at camp all day and all night. Most children w____  attend overnight camp are between the ages of about six and sixteen.
    Children s____  at an overnight camp for between one and eight weeks. P____  can pay less than one-hundred dollars a week for an overnight camp. Or they can pay more than seven-hundred dollars a week.

梅尧臣的《鲁山山行》中描写山间种种景象的诗句是：____，____。以从云外传来的一声呜叫来告诉诗人有住家的地方还很远很远的诗句是：____，____。