Answer:
-47 J
Explanation:
Given that,
Heat loss = -76 J (negative for loss)
Work done by the surroundings = -29 J
We need to find the change in internal energy of a system.
The first law of thermodynamics is given by :

W is work done by the system
Putting all the values,

Hence, the change in internal energy is -47 J.
C is the breakdown of rock and soil on earths surface. Think of the grand canyon.