Now we add a plexiglass atmosphere above the ground (as in class). The set-up of this environment has the following properties: a. The atmosphere is completely transparent to the incoming solar radiation (the atmosphere does not absorb any solar radiation) b. The atmosphere's temperature is Tal and it emits IR radiation according to the Stefan-Boltzmann law both upward and downward, by the same amount c. The atmosphere completely absorbs the IR radiation coming from the ground d. The ground temperature is T9 and the ground emits IR radiation according to the Stefan Boltzmann law e. The ground completely absorbs all radiation it receives At the top of the atmosphere, solar radiation F (the same value as QB) goes down, while an upward IR radiation, originated from the atmosphere, goes out to space. From the energy balance at the top of the atmosphere, determine Ta in (K)