Ok, so we need to find the unit rate of 15 degrees in 2 hours.
this is a very simple question, it says here that in 2 hours, there are 15 degrees.
Thus we need to find the unit rate of this given situation per hours.
=> hour many hours are there? The answer is 2
so let us divide 2 by 15 to get the unit rate of the given situation
=> 15 degrees / 2 hours
=> 7.5 degrees / hours
Thus, the unit rate of 15 degrees per 2 hours is 7.5 degrees per hour.