地块 | 甲 | 乙 | 丙 | 丁 | 戊 |
施肥情况 | CO(NH2)2 | KH2PO4 | NH4H2PO4 | (NH4)2SO4 | 不施肥 |
小麦收获 | 55.56 | 67.26 | 55.88 | 55.44 | 55.11 |
据表判断该农田最可能缺少的元素是( )
A.钾 | B.氮 | C.磷 | D.硫 |
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