On December 31, Year 3, Mueller Corp. acquired 80% of the outstanding shares of Wilson Inc. for a total cost of $240,000. The carrying amount of Wilson's assets, liabilities, and equity was equal to fair value except for the following: As at December 31, Year 3, the equipment and patent had an estimated useful life of six and eight years, respectively. The long-term debt Mueller uses the cost method to account for its investment in Wilson. The book values of selected accounts for the year ended December 31 , Year 7 were as follows: (a) Prepare a schedule of changes to the acquisition differential for the four year period ending December 31, Year 7. (b) Calculate consolidated net income attributable to the parent, ending retained earnings and noncontrolling interest at December 31 , Year 7