Answer:
c. are renewable
Explanation:
There are many energy sources that the humans have learned to use and exploit. Some resources are non-renewable, while some a re renewable. The non-renewable tend to be cheaper for the time being, and they also tend to produce more energy, but the problem is that the reserves will eventually run out. On the other side, the renewable resources are constantly out there, and they can not be spent, which gives them the advantage on the long run.
The alternative energy sources have been more and more in the focus, especially when it comes to the more developed nations. The main reasons for this are that the fossil fuels will eventually run out, and that they are more environment friendly. This has led to development of technology that is able to harvest energy from the sun, water, and wind, all which are natural resources that are constantly present and can not be spent. Some nations have invested so much in these resources that they have gradually started to replace the fossil fuels, with the end goal being stopping the usage of the fossil fuels totally.
Answer:
The Earth has different temperatures because they depend on how far away the sun is to the planet (as well as many other factors of atmosphere, altitude, etc.) If the sun is closer to one part of the Earth it will be hotter than other places where the sun is not as close.
Explanation:
