求满足下列条件的∠A的度数（精确到1″）：

（1）cosA=0.8607；

（2）tanA=56.78．

某植物种群中，AA基因型个体占30%，aa基因型个体占20%，回答下列问题

（1）植物的A、a基因的频率分别是____ 、____ ．

（2）若该植物自交，后代中AA、aa基因型个体分别占____ 、____ 　．这时，A、a的基因频率分别是　____ 、____ 　．

（3）依据现代生物进化理论，这种植物在两年中是否发生了进化？____ ，原因是____ ．

（4）由此可知，生物进化的基本单位是____ ，进化的实质是____ ．

根据短文内容和所给中文提示，写出短文空白处各单词的正确形式。每空限填一词。
    These days, a Chinese girl's travel diary has become a hit online.
    Zhao Xing, with only a____ （地图）, a travel bag and 30 Yuan, left the Chinese mainland for the ____ （第一）time to Taiwan. At the ____ （机场）, she was helped by a man who even told her his phone number. A bus driver was kind enough to ____ （叫醒）her up when she fell asleepon the ride.
    In Taiwan, Zhao told the man who ____ （给）her a ride that she was from Beijing. The man asked if there was____ （任何事）else he could do to help make her journey____ （更好的）.
  “After coming back and thinking over everything I've experienced, I realized that the people impressed me the most, not the beautiful scenes or tasty food,” Zhao ____ （写）in her online diary.
    From Beijing to Taiwan, so close, so ____ （遥远的）away. Zhao's wish is to encourage others to realize their ____ （自己的）dreams of making the world a smaller, more friendly place for all.