选项 | 劳动项目 | 化学知识 |
A | 用活性炭自制冰箱去味剂 | 活性炭具有吸附性 |
B | 用小苏打发面蒸馒头 | NaHCO3能做面食的发酵剂 |
C | 用“雕牌”洗洁精清洗餐具 | 洗洁精具有乳化作用 |
D | 盆花叶片发黄,施用氯化钾 | 氮肥壮叶 |
A.A | B.B | C.C | D.D |

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

