
1.太平洋铁路甲段建设中遇到的主要自然问题是( )
A.终年炎热,大片沙漠 | B.高寒、缺氧、低气压 |
C.沟壑纵横,黄土广布 | D.山岭众多,地势险峻 |
A.家庭农场规模化生产 | B.牧业生产高度现代化 |
C.大面积使用滴灌技术 | D.山地垂直农业一体化 |

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

