(1)我国所产棉花纤维柔长、洁白有光,棉花属于
(2)袁隆平院士的研究团队曾在我国高盐碱地区试种“海水稻”,高盐碱地区土壤的pH超过8.5,土壤pH越大、其碱性越
a. NH4NO3 b. Ca3(PO4)2 c. KNO3 d. KCl
(3)垃圾分类,意义重大。空易拉罐是
a.厨余垃圾 b.可回收垃圾 c.有害垃圾 d.其他垃圾
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