Since the aluminum bar is not an isolated system, the second law of thermodynamics cannot be applied to the bar alone. rather, it should be applied to the bar in combination with its surroundings (the lake). assume that the entropy change of the bar is -1238 j/k . what is the change in total entropy δstotal?

It really doesn't matter for any of the questions that you've listed.

Answerthe energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.explanationwe define electric potential as the ratio electric potential energy to the charge,    then the following gives us the potential difference,      the formula  may be on your formula sheet.the change in electric potential energy would be the energy that would needed to move it from point a to point b. solving for that, we get    using q = 8.00  × 10⁻¹⁹ c and  δv = 2.00 v, we get    the energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.