Hey there!
The answer to your question is: Iron
There is a very high concentration of iron and other metals in the mesosphere. There is a further buildup of these metals when meteorites burn up in the atmosphere and release such metal atoms.
Thank you!
Answer:

Explanation:
We are given that three resistors R1, R2 and R3 are connected in series.
Let
Potential difference across 
Potential difference across 
Potential difference across 
We know that in series combination
Potential difference ,
Using the formula

Hence, this is required expression for potential difference.
Answer: The partial pressure of
if the total pressure of the mixture is 3.9 atm is 0.975 atm
Explanation:
According to Raoult's law, the vapor pressure of a component at a given temperature is equal to the mole fraction of that component multiplied by the vapor pressure of that component in the pure state.

where, x = mole fraction of nitrogen in solution = 0.25
= partial pressure of nitrogen = ?
= Total pressure = 3.9 atm
Putting in the values :

The partial pressure of
is 0.975 atm
Answer:
Efriction = 768.23 [kJ]
Explanation:
In order to solve this problem we must use the principle of energy conservation. Where it tells us that the energy of a system plus the work applied or performed by that system, will be equal to the energy in the final state. We have two states the initial at the time of the balloon jump and the final state when the parachutist lands.
We must identify the types of energy in each state, in the initial state there is only potential energy, since the reference level is in the ground, at the reference point the potential energy is zero. At the time of landing the parachutist will only have potential energy, since it reaches the reference level.
The friction force acts in the opposite direction to the movement, therefore it will have a negative sign.

where:

m = mass = 56 [kg]
h = elevation = 1400 [m]
v = velocity = 5.6 [m/s]
![(56*9.81*1400)-E_{friction}=\frac{1}{2}*56*(5.6)^{2}\\769104 -E_{friction}= 878.08 \\E_{friction}=769104-878.08\\E_{friction}=768226[J] = 768.23 [kJ]](https://tex.z-dn.net/?f=%2856%2A9.81%2A1400%29-E_%7Bfriction%7D%3D%5Cfrac%7B1%7D%7B2%7D%2A56%2A%285.6%29%5E%7B2%7D%5C%5C769104%20-E_%7Bfriction%7D%3D%20878.08%20%5C%5CE_%7Bfriction%7D%3D769104-878.08%5C%5CE_%7Bfriction%7D%3D768226%5BJ%5D%20%3D%20768.23%20%5BkJ%5D)