Much of the mineral and oil wealth of the northern territories are reserved for emergency.
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.
I believe the final answer is correct. Water is a desert's scarcest recourse. <span />
Answer:
Two stars (a and b) can have the same luminosity, but different surface area and temperature if the following condition is met:
(T_a^4)(R_a^2) = (T_b^4)(R_b^2)
Explanation:
The luminosity of a star is the total energy that produces in one second. It depends on the size of the star and its surface temperature.
L = σ(T^4)(4πR^2)
L is the luminosity f the star, T is the temperature of the surface of the star and R is its radius.
Two stars can have the same luminosity if the relation between the radius and the surface temperature is maintained.
To see this lets suposed you have 2 stars, a and b, and the luminosities of each one of them:
L_a = σ(T_a^4)(4πR_a^2)
L_b = σ(T_b^4)(4πR_b^2)
you can assume that L_a and L_b are equal:
σ(T_a^4)(4πR_a^2) = σ(T_b^4)(4πR_b^2)
Now, you can cancel the constants:
(T_a^4)(R_a^2) = (T_b^4)(R_b^2)
as long as this relation between a and b is true, then the luminosity can be the same.
Arenal Volcano is in the middle of the continent
