Let's go through the questions one by one:

a. $2^3 + 3^3$

• $2^3 = 8$
• $3^3 = 27$

So, $2^3 + 3^3 = 8 + 27 = 35$

b. $2 \cdot 3^2$

• $3^2 = 9$
• $2 \cdot 9 = 18$

So, $2 \cdot 3^2 = 18$

c. $-2 \cdot 3^2$

• $3^2 = 9$
• $-2 \cdot 9 = -18$

So, $-2 \cdot 3^2 = -18$

Final answers:

a. $35$
b. $18$
c. $-18$

Let me know if you'd like more detailed explanations!

Related questions:

1. What is the general rule for exponents and multiplication?
2. How do we handle negative numbers when using exponents?
3. What is the difference between a positive and negative base when using exponents?
4. Can you explain why $(-3)^2$ is different from $-(3^2)$?
5. How does the order of operations (PEMDAS) affect exponentiation?

Tip: Always evaluate exponents first before performing addition, subtraction, or multiplication when following the order of operations.