Answer:
The layer of greenhouse gases is permeable to one side and not permeable to another side.
Explanation:
Greenhouse gases such as carbondioxide, methane and water vapors etc formed a layer which allow the sun radiation to the earth surface but when these radiation reflected back, this layer traps these reflected radiation and the radiation remain suspended in air which heat up the particles present in the air and increases the temperature which causes global warming of earth surface. This phenomenon is also called greenhouse effect and it is also very useful in growing crops in cool seasons. So this layer is permeable from one side and not permeable from another side.
Answer:
B) Extremely cold climate conditions made it difficult to live in the region
Explanation: In places where there are countless mountain ranges, there is bound to be isolation to the point where the people that already reside there would develop their own language, culture, and mannerisms. Northern Europe is filled with mountains and cold climate. Many people from other regions in Europe would have a hard time adjusting to the harsh conditions like the natives.
Answer: D. changes direction
Explanation: A lens works by refraction: it bends light rays as they pass through it so they change direction.
Hope this helps
