
1.“雪球”时代的结束,是因为寒武纪的火山大爆发能( )
A.释放巨量热能,直接增加大气温度 |
B.破坏臭氧层,到达地面紫外线增多 |
C.释放火山灰物质,吸收地面辐射 |
D.增加大气中CO2浓度,起保温作用 |
A.花岗岩 | B.玄武岩 |
C.石灰岩 | D.变质岩 |

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

