ANS:A - 1

To convert from kilocalories per kilogram degree Celsius (kcal/kg. °C) to British thermal units per pound degree Fahrenheit (BTU/lb. °F), we need to use conversion factors that account for both the difference in units (kilocalories to BTUs and kilograms to pounds) and the difference in temperature scales (Celsius to Fahrenheit). First, let's address the conversion factors:

• 1 kcal/kg. °C is equivalent to 1 kilocalorie of energy absorbed per 1 kilogram of substance per 1 degree Celsius temperature change.
• To convert from kilocalories to BTUs, we need to multiply by the conversion factor 1 kcal = 3.968 BTU.
• To convert from kilograms to pounds, we need to use the conversion factor 1 kilogram = 2.20462 pounds.
• To adjust for the temperature difference, we need to account for the different scales: 1 °C = 1.8 °F.

Now, let's combine these conversion factors: 1 kcal/kg. °C=1 kcal×3.968 BTU1 kcal×2.20462 lb1 kg×11.8 (to adjust for temperature scales)1 kcal/kg. °C=1 kcal×1 kcal3.968 BTU​×1 kg2.20462 lb​×1.81​ (to adjust for temperature scales) Solving this, we get: =1×3.968×2.20462×11.8 BTU/lb. °F=1×3.968×2.20462×1.81​ BTU/lb. °F ≈4.97 BTU/lb. °F≈4.97 BTU/lb. °F So, 1 kcal/kg. °C is approximately equivalent to 4.97 BTU/lb. °F. Therefore, the correct answer should be: (c) 4.97