To determine whether the statement $D' \subset E$ is true or false, let's break it down step by step.

Definitions and Steps:

1. Universal Set (U):
   $U = \{p, q, r, s, t\}$

2. Set $D$:
   $D = \{q, s, p, r\}$

3. Complement of Set $D$ (denoted as $D'$):
   The complement of $D$ in $U$ is the set of elements in $U$ that are not in $D$. $D' = U \setminus D = \{t\}$

4. Set $E$:
   $E = \{r, t\}$

5. Subset Relation:
   Now, we check if $D' \subset E$.
   $D' = \{t\}$ and $E = \{r, t\}$.

   Since all elements of $D'$ (which is just $\{t\}$) are in $E$, we conclude that $D' \subset E$.

Conclusion:

The statement $D' \subset E$ is true.

Would you like more details or have any questions?

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Here are 5 related questions to consider:

1. How do you find the complement of a set in a universal set?
2. What are the differences between proper subsets and regular subsets?
3. Can a set be a subset of itself?
4. How do you determine if a statement involving sets is true or false?
5. How would the result change if $U$ were a different universal set?

Tip: A subset $A$ of a set $B$ means every element of $A$ is also in $B$.