Find some combination of G, the speed of light c, and some arbitrary mass M, that has units of length. Then evaluate your expression for the mass of the Sun (that is, find the characteristic length associated with that mass). Give your answer in units of km.
The Attempt at a Solution
G has units (m^3)/[(kg)(s^2)]
To get rid of the m^2, I can take a square root, but how can I get rid of the time in seconds in the denominator?