读南半球中纬度平原地区某河段示意图,完成下面小题。
1.图中a、b、c、d四地中流水侵蚀作用较强的有( )
A.a、b | B.b、c | C.a、c | D.b、d |
A.支流流速缓慢 | B.位于河流干流凹岸 |
C.干流侧蚀作用强 | D.汇入处河床比降大 |
A.下游新建防洪大堤 | B.上游建大型水库 |
C.下游河道不断疏通 | D.上游种植业发展迅速 |
同类型试题
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2