Answer:
It was the ancient Greeks who first developed the passive solar concepts that the Romans adopted, but the Romans used their engineering and design skills to improve the technique. Passive-solar buildings are built based on the orientation of the sun's path and use the sun's rays to heat the interiors.
"There ain't no such thing as a free lunch" expresses the idea that even if something seems like it is free, there is always a cost, no matter how indirect or hidden.
The blacks would be happy that the Union were winning because they were one step away from freedom from slavery
