The hard snow walls of an igloo are good insulators that keep in body heat and also the heat generated by oil lamps, these are known as qulliq. This is why traditional igloos are commonly made out of snow rather than ice and this is because solid ice does not retain heat as well as blocks of compressed snow. In addition, the walls block the wind, which is often so bitter that it can make freezing temperatures feel many degrees colder. Also, insulation capabilities actually increase a few days after construction. Body heat and sun exposure cause the inside of the igloo to melt ever so slightly. When the igloo is unoccupied during hunting expeditions, the melted snow freezes over, turning into ice. Gradual thawing and refreezing turns the entire structure to solid ice, making it not only superstrong, but warmer than ever.
I would go with issues that contributed to the civil war.
Racism and Women's rights were a huge controversy during the civil war and the 15th amendment gives every one the right to vote, no matter what race, gender, or past slavery.
Sorry about the late answer!
Hippocrates was the first to separate medicine from philosophy & HE believed in the importance of diet & exercise for a healthy body
