Answer:between 25 and 40 degrees Fahrenheit
Explanation:
Heat pumps do not operate as efficiently when temperatures drop to between 25 and 40 degrees Fahrenheit for most systems. A heat pump works best when the temperature is above 40. Once outdoor temperatures drop to 40 degrees, heat pumps start losing efficiency, and they consume more energy to do their jobs.
NA and CL
Na and F
IONIC OCCURS BETWEEN METALS AND NON METALS
Mass is the amount of matter in an object, and weight is the downward pull on an object due to gravity. Which property of physical changes explains why matter is conserved in a physical change? The bonds between atoms do not break; it is only the arrangement that changes.
hope I helped! :)
Answer: Plate movement is thought to be driven by a combination of the motion of the seafloor away from spreading ridges due to variations in topography and density changes in the crust.
Hope this helps