1.) We are given:
To find the domain, we set:
Now solve for .
Since the function is increasing as T increases, you will find the lower limit of the range by evaluating the function at the smallest value of T and the upper range is unbounded.
Once we get this problem done and understood, I will move on the the next. I like to take them one at a time, and also solving this one will help you with the next one.