Final answer:
The minimum Fahrenheit temperature to maintain at least 5°C is 41°F. The Celsius to Fahrenheit conversion formula is used to calculate this value. The correct answer is (d) 41°F.
Step-by-step explanation:
To find the minimum Fahrenheit temperature that must be maintained to keep a system at least 5°C, use the formula for converting Celsius to Fahrenheit:
Fahrenheit (F) = (Celsius (C) × 9/5) + 32
Plugging in 5°C into the formula, we get:
F = (5 × 9/5) + 32 = 41°F
Therefore, the minimum Fahrenheit temperature that should be maintained is 41°F to ensure that the system's temperature does not fall below 5°C. Hence, the correct answer is (d) 41°F.