Btu (3.9°C)
The Btu (3.9°C) is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit at the temperature where water reaches its maximum density which occurs at approximately 3.9°C (39°F).
Newton-meters
A newton-meter (Nm) is primarily used to quantify torque which is the rotational force applied to an object. It is the force of one newton applied perpendicularly to a lever arm one meter long.