By the second law of thermodynamics:
Heat can not spontaneously flow from cold regions to hot regions without external work being performed on a system.
Heat transfer is the passage of thermal energy from a hot ( t B = 80° C ) to a colder body ( t A = 40° C ).
Answer: B ) Heat flows from object B to object A.
Answer: 27 is A and 28 is C.
Explanation: I’ll explain 28 but not 27 because that’s just definitions.
In CuSO4 there is a Cu, an S, and 4 O molecules. Add them up you get 6.