The graph below plots the escape velocity of each planet along the vertical axis,and its surface temperature along the horizontal.The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases.Which gas(es) plotted in the diagram could be retained in the atmosphere of Mars? 
Definitions:
Alleviation
Alleviation refers to the act of making something, such as suffering or a problem, less severe or more bearable.
Social Enterprise
A business model that aims to solve social problems, improve communities, provide people access to employment and training, or help the environment using revenue generated from its operations.
Fundraising Methods
Various strategies and approaches used by organizations, especially nonprofits, to collect financial support from donors and the public.
Hybrid Organizations
Entities that combine characteristics of both non-profit and for-profit organizations, often pursuing social goals with business methods.
Q1: The "framework" of molecules important for life
Q6: The surfaces of old icy satellites of
Q8: For an observer on Uranus,the ecliptic passes
Q12: The particles in the rings of Neptune
Q17: The material that accretes onto a neutron
Q20: Outgassing produces gas rich in carbon dioxide,nitrogen,and
Q51: Alec is almost completely dependent on his
Q62: Meteorites seem to come from both the
Q101: Teri's doctor has recommended that she take
Q109: Which of the following is an example