①饼干在空气中长久放置会变软,说明空气中含有
②蜡烛在集气瓶中燃烧一会儿后,要自动熄灭,说明燃烧耗尽了空气中的
③澄清的石灰水长期暴露在空气中会变浑浊,说明空气中含有
④“独钓寒江雪”,是因为冬天在冰面上敲出一个洞口,能够吸引很多鱼向洞口游动。说明鱼儿需要到水面来呼吸

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

