
1.土壤覆盖在地球的表面,它是动植物和人类赖以生存的“
2.把土壤捻一,感觉土壤很湿润,这说明土壤中有
3.如图1所示,把水倒进盛有土壤的玻璃杯中,用玻璃棒充分搅拌,产生了气泡,这说明土壤中有
4.地面上死亡的动物、植物腐烂后,在土壤中形成黑褐色物质就是

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

