Answer:

Explanation:
The heat transfer through brick wall is:



The heat flow in a 18.6-h period is:




Answer:
atoms and neutrons
Explanation:
electrons have a negative charge
protons have a positive charge
cations are positive ions
anions are negative ions
In the future ? Well, there's no technological reason why it couldn't be 100%.
When a valence electron absorbs energy in the form of heat or light it uses that energy to jump to an excited state (outer level)