Answer:
When you have iodine gas at 200 degrees, the temperature and thus pressure as so high, that when cooling down you enter the liquid phase. And when some of this gas then condenses, the pressure drops. So the remaining part of the gas can sublime.
Step-by-step explanation:
The correct answer is Hector's, 4 degrees, and Gale's.
One solution
The two (or more) equations would only intersect once
No solution
Lines never intersect
The lines are parallel
Infinite solutions
The lines are the exact same
That’s all the characteristics I know