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 is due on January 1, Year 9 . There was a goodwill impairment loss of $3,000 in Year 5 . There were no other impairment losses. 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: Required: (a) Prepare a schedule of changes to the acquisition differential for the four year period ending December 31, Year 7. (Leave no cells blank - be certain to enter "0" wherever required. Omit $ sign in your response. Negative/Deductible amounts should be indicated by a minus sign.) (b) Calculate consolidated net income attributable to the parent, ending retained earnings and non-controlling interest at December 31 , Year 7. (Omit $ sign in your response.)