What is the statement of the first law of thermodynamics?
A. The change in internal energy of a system equals the product
of net energy transferred by heat into the system and the net work
done by the system.
B. The change in internal energy of a system equals the net
energy transferred by heat into the system divided by the net work
done by the system.
C. The change in internal energy of a system equals the sum of
net energy transferred by heat into the system and the net work
done by the system.
D. The change in internal energy of a system equals the net
energy transferred by heat into the system minus the net work done
by the system.