Jin knows that the initial internal energy of a closed system is 78 J and the final internal energy is 180 J. He also knows that 64 J of energy are used to do work. To find the heat added to the system, Jin completes the steps below.

1. Add the initial internal energy plus the final internal energy to find the change in internal energy.
2. Add the change in internal energy to the energy used to do work.
3. Write the answer in joules.

Which best describes Jin's error?

For step 1, he should have used 180 J as the change in internal energy.
For step 1, he should have subtracted 78 J from 180 J to find the change in internal energy.
For step 2, he should have subtracted the change in internal energy from the energy used to do work.
For step 2, he should have subtracted the energy used to do work from the change in internal energy.