Answer:
The earth is 4 billion years old.
Explanation:
To solve this problem we will apply the definition of the ideal gas equation, where we will clear the density variable. In turn, the specific volume is the inverse of the density, so once the first term has been completed, we will simply proceed to divide it by 1. According to the definition of 1 atmosphere, this is equivalent in the English system to

The ideal gas equation said us that,
PV = nRT
Here,
P = pressure
V = Volume
R = Gas ideal constant
T = Temperature
n = Amount of substance (at this case the mass)
Then

The amount of substance per volume is the density, then

Replacing with our values,


Finally the specific volume would be


-- Kinetic energy is the energy of mass in motion. The amount is determined by the mass of whatever is moving, and its speed.
-- Potential energy is the energy that's stored up in some form, not being used yet but ready to be used when you want it.
For example, one form of it is <u><em>chemical</em></u><em> </em>potential energy, like in a battery, or a match. You get the energy out of a battery when you connect it to a motor or a light. You get the energy out of as match when you make the tip hot and it flares up.
This question is asking about <u><em>gravitational</em></u> potential energy. An object has stored energy just by being up high, like a bowling ball on a shelf. You get the energy out of it just by dropping it ... possibly enough to crack the floor !
The amount of this kind of potential energy is determined by the mass of the object, and how high up it is.
-- Getting the answers from other people doesn't help you a bit, until you understand them and can answer the question on your own.
Since it is restricted at both ends, λ/2 = length of string
λ/2 = 1.5m
λ = 1.5*2 = 3m