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1.   Spectrum A contains more shorter wavelengths than longer wavelengths.  This mixture will produce a "cool" white color.

3.   Think of a black car (low reflectivity) and a white car (higher reflectivity) sitting in the sun.  The black car will absorb more sunlight than the white car.  To be in energy balance it must emit more energy than the white car.  To be able to emit more energy it will need to be warmer than the white car.

4.   The fall equinox was about 3 weeks ago.  We are on our way toward the winter solstice.

5.   The atmosphere is absorbing 3 units of energy and must therefore emit 3 units.  The ground is absorbing one unit of sunlight and emitting 3 units of IR radiation.  It therefore needs 2 out of the 3 arrows that the atmosphere is emitting to be in balance.  The remaining 1 of 3 units emitted by the atmosphere goes upward into space.  Note at the top of the figure that 2 units of sunlight arrive at the top of the atmosphere and 2 units of IR radiation leave the atmosphere headed for out space.

6.   If you look at just what is happening at the ground, you will notice that both figures are absorbing 2 units of sunlight and 1 unit of radiation from the atmosphere.  The ground is emitting 3 units of energy in both figures.  The situation at the ground is the same in both figures.  The ground temperature in both figures must be the same.