A brass ring of diameter 10.00 cm at 20 degrees Celsius is heated and slipped over an aluminum rod of diameter 10.01 cm at 20 degrees Celsius. Assuming the average coefficients of linear expansion are constant, a) to what temperature must this combination be cooled to seperate them? b) What if the aluminum rod were 10.02 cm in diameter? I don't know where to start for this problem. Any help will be much appreciated. Thx in advance!