1. The temperature is distributed to the body to protect the more important organs and parts of the body. The legs and the arms are the least warm.
2. In order to survive, the chest and head must stay warm. The first areas of a person's body to go are their legs and arms, so that is why that part is the coldest. The temperature is distributed this way in order to keep the person's chest warm.
3. While cold, a person's skin may be blue. But when a person is warming up, their skin returns to the "redish" color again because blood flow is better and the individual's circulation has reached better conditions.
4. This person would begin to warm up to 37 C once again. It would first reach 37 C at the second layer, and then to the third. Warming up would cause the feet and arms to return to normal conditions and color.
Best of luck.