1a 鳞片较大,背鳍延展至尾部 2 1b 鳞片细小,背鳍未延至尾部 3 2a 头部较短,嘴边无短须 甲 2b 头部较长,嘴边有短须 乙 3a 体表深色,有斑纹 丙 3b 体表白色,无斑纹 丁 |
A.鲫鱼 | B.鲤鱼 | C.白鲢鱼 | D.鳙鱼 |
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