1. Problem: Convert the decimal 0.6 to a percentage. 2. Formula: To convert a decimal to a percentage, multiply by 100 and add the % sign. 3. Calculation: $$0.6 \times 100 = 60$$ 4. Explanation: Multiplying 0.6 by 100 shifts the decimal two places to the right, giving 60%. So, 0.6 as a percentage is 60%. Final answer: c. 60%