Part 1: If it has enough kinetic energy, a molecule
at the surface of the Earth can escape the
Earth’s gravitation.
The acceleration of gravity is 9.8 m/s², and the Boltzmanns’ constant is 1.38066 × 10−23 J/K.
Using energy conservation, determine the
minimum kinetic energy needed to escape in
terms of the mass of the molecule m, the
free-fall acceleration at the surface g, and the
radius of the Earth R.
1. Kmin = 1/3mgr
2. Kmin = mgr
3. Kmin = 1/2mgr
4. Kmin = 1/sqrt2 mgr
5. Kmin = 2mgr
Answer is 2 mgr I got it correct

Part 2: Calculate the temperature for which the minimum escape energy is 5 times the average kinetic energy of an oxygen molecule. Answer in units of K.