读某区域等高线图,该地区的主要地形类型是( )
A:盆地
B:山地
C:高原
D:丘陵
求
(Ⅰ)函数f(x)的解析式;
(Ⅱ)函数y=Acos(ωx+ϕ)的单调递增区间.
—I think teenagers should be allowed to make their own decisions when they have problems at school.
—_______. They're not calm enough, after all.