How much did pretax income change because of the decision on December 31, current year?

Please show how you got the answer and the actual amount it changed.

Required information (The following information applies to the questions displayed below.) Pacific Company sells electronic test equipment that it acquires from a foreign source. During the yea records reflected the following: Beginning inventory Purchases Sales (52 units at $24,630 each) Units 23 39 Unit Cost $11,600 10,100 Total Cost $ 266,800 393,900 Inventory is valued at cost using the LIFO inventory method. 3a. How much did pretax income change because of the decision on December 31, current year? 3b. Assuming that the unit cost of test equipment is expected to continue to decline during the following ye income manipulation? Complete this question by entering your answers in the tabs below. I