find domain and range

Since Domain are all the inputs possible, and square root cannot do negative numbers, x can't go below 3, otherwise the thing will be a complex number. So, your domain is:


Then, your range has to be greater than 0 because a principal square root symbol, if passed a positive number will return a positive answer. So, your range should be:


But, then you add 2 to it, so it then turns into:

The answer is that the rate of change is $50 per 1 monthhope this ; )