Answer:
Hydrogen in the core of the star is converted to helium by nuclear fusion. When the hydrogen supply in the core begins to run out, and the star is no longer generating heat by fusion, the core becomes unstable and contracts.
15 degrees (1 degree every 4 minutes)
Answer is C. Deegeees north and south of the equator
The answer is that they arrived in Mesoamerica in the 13th century
It seems you need to move the decimal three times over, then you round the number. So the answer would be 5.5 x 10^3.
