## Fill-in-the-blank proofs
for Section 3.3

**Claim:**
For all sets A and B, (A ∩ B) ⊆ A.

*Proof*.* *Click here.

**Claim:**
For all sets A and
B, B ⊆ (A ∪ B).

*Proof*.* *Click here.**
**

** Claim:**
For all sets A and
B, if A ⊆ B, then (A ∪ B) ⊆ B.

* Proof*.* *Click here.

**Claim:**
For all sets A,
B and C, if A ⊆ B and A ⊆ C, then A ⊆ (B ∩ C).

* Proof*.* *Click here.

**Claim:**
For all sets A, B and C, (A ∩ B) ∪ (A ∩ C) ⊆ A ∩ (B ∪
C).

* Proof*.* *Click here.