下图表示我国甲、乙两城春分日(图中a点)到夏至日(图中e点)正午太阳高度之差ΔH(ΔH=H甲-H乙)的时间变化图。完成下面小题。

1.根据题意,下列推断正确的是( )
A.甲城纬度高于乙城 | B.a到b期间两地正午太阳高度同步变小 |
C.b到d期间两地昼长同时增大 | D.c点时两地正午太阳高度和昼长都相等 |
A.北京(40°N) | B.杭州(30°16'N) | C.三沙(16°50'N) | D.海口(20°N) |

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

