（Ⅰ）讨论函数F（x）=f（x）+ax（a∈R）的单调性；

（Ⅱ）若∀x∈R，不等式e^xf（x）≤c（x﹣1）+1恒成立，求实数c的取值范围．

    Two farmers were on their way home one evening after a hard day's work．Both were tired．They happened to look up at the sky and saw a black cloud overhead．
    "Ah!" said one farmer, "tomorrow we shall have rain and the rice will grow well．" The second answered, "Nonsense （胡说）, the rain will only kill the crops （庄稼）．"
    So they began to fight．Just then a third farmer came along and asked them why they were quarreling（争吵）．Both farmers explained about the black cloud．
    "What cloud?" asked the third farmer．They all looked at the sky．The cloud was no longer there．

烛焰通过凸透镜在另一侧的光屏上成一个倒立放大的像，如果保持凸透镜的位置不变，只将蜡烛和光屏的位置相互交换，那么（   ）

方方从家到图书馆，用了30分钟，她平均每分钟走 $\frac{1}{3}$ 千米，她家距离图书馆有多少千米？