For a given function f(x), the domain is the set of possible values of x that we can use and the range is the set of the possible values of f(x).
For both points we will find that the answer is:
"We only can evaluate the function with integer values of d."
a) Here we have the function:
A(d) = 2 + 0.25*d
The first thing we want to answer is:
"explain why the domain does not contain the value d=2.5 "
We know that at the end of each day the kids get's the $0.25, so at d= 2.5 there two days and a half, and because only 2 nights passed, at this moment the kid only got the money two times.
So for d = 2.1
d = 2.5
d = 2.7
etc
We would get the exact same total money, thus we only can evaluate the function with integer values of d.
b) Why the range does not include the value A = $3.10?
Remember that d can only be an integer number.
Now let's solve:
A(d) = 3.10 = 2 + 0.25*d
3.10 - 2 = 0.25*d
1.10 = 0.25*d
1.10/0.25 = d = 4.4
So we only can get A = $3.10 if d = 4.4, and remember that d only can be a whole number, this is why the range does not include the value $3.10
If you want to learn more, you can read:
brainly.com/question/1632425
elements. 
(factorial) of the