1. **Problem:** Identify the greatest common factor (GCF) for each expression. 2. **Formula:** The GCF is the largest factor that divides all terms in the polynomial. 3. **Work:** a. $15c^2 - 65c$ Factors of 15 and 65 are 15 and 65; common factor is 5. Both terms have at least one $c$, so GCF is $5c$. b. $16x^2 - 64x + 11$ Factors of 16 and 64 are 16; 11 is prime and does not share factors. No common factor for all three terms, so GCF is 1 (none). c. $8m^2 + 14m - 4$ Factors of 8, 14, and 4 are 2. No common variable in all terms, so GCF is 2. **Final answers:** a. $5c$ b. None c. $2$