Set Operations Logic
1. **Find all subsets of C where C = {3, 7}**
The subsets of a set with $n$ elements are $2^n$. Since $C$ has 2 elements, it has $2^2 = 4$ subsets.
These subsets are: $\emptyset$, ${3}$, ${7}$, ${3,7}$.
2. **Find $A \cap B$ with $A = \{1, 3, 5\}$ and $B = \{3, 5, 7\}$**
$A \cap B$ is the set of elements common to both $A$ and $B$.
Common elements are $3$ and $5$, so $A \cap B = \{3, 5\}$.
3. **Find $(A - C) \cup B$ where $C = \{3, 7\}$**
First, $A - C$ is the set of elements in $A$ but not in $C$.
$A = \{1, 3, 5\}$ and $C = \{3, 7\}$ so $A - C = \{1, 5\}$.
Now, $(A - C) \cup B = \{1, 5\} \cup \{3, 5, 7\} = \{1, 3, 5, 7\}$.
4. **Given $Y \subset X$, $|X| = 16$, $|Y| = 5$, and $|X'| = 8$, find:**
i. $|Y'|$
By definition of complement, $|X'| = 8$ means the universal set $U$ has $|U|$ elements such that:
$$|X'| = |U| - |X| = 8\implies |U| = 8 + 16 = 24$$
Since $Y' = U - Y$,
$$|Y'| = |U| - |Y| = 24 - 5 = 19$$
ii. Number of elements in the universal set = $|U| = 24$.
5. **Verify propositional logic equivalences via truth tables:**
i. $\sim (p \wedge q) = (\sim p) \lor (\sim q)$ (De Morgan's law)
ii. $\sim (p \lor q) \lor (\sim p \wedge q) = \sim p$
iii. $\sim (\sim (p \lor q) \lor \sim (p \lor r)) = p \lor (q \wedge r)$
Verification involves constructing truth tables for $p, q, r$ and checking both sides yield the same truth values in all cases.
**Final answers:**
1. Subsets of $C$: $\emptyset, \{3\}, \{7\}, \{3,7\}$
2. $A \cap B = \{3, 5\}$
3. $(A - C) \cup B = \{1, 3, 5, 7\}$
4. (i) $|Y'| = 19$
(ii) $|U| = 24$
5. Verified by truth tables (equivalences hold).