Final answer:
Set e is not a subset of set d. Set d is a subset of set f. Set f is not a subset of set e. Set f is not a subset of set d.
Step-by-step explanation:
To determine if set e is a subset of set d, we need to check if all elements of e are also in d.
d = {b, a, c, k}
e = {t, a, s, k}
As we can see, not all elements of e are in d; specifically, 't' and 's' are not in d. Therefore, e is not a subset of d.
For part b, set d is a subset of set f if all elements of d are also in f. In this case, 'b', 'a', and 'k' are all in f, so set d is a subset of set f.
For parts c and d, the same comparison can be made. Since set f does not contain all elements of set e, f is not a subset of e, and f is also not a subset of d.