PLEASE EXPLAIN STEP BY STEP

Brady Construction Company contracted to build an apartment complex for a price of $6,300,000. Construction began in 2018 and was completed in 2020. The following is a series of independent situations, numbered 1 through 6, involving differing costs for the project. All costs are stated in thousands of dollars. Estimated Costs to Complete (As of the End of the Year) Costs Incurred During Year Situation 2018 2019 2020 2018 2019 2020 11,630 2,520 1,290 3,810 1,290 2 1,630 1,290 2,920 3,810 2,920 3 1,630 2,520 2,640 3,810 2,540 4 630 3,130 1,260 4,410 940 5 630 3,130 2,210 4,410 2,540- 6 630 3,130 3,100 5,855 2,870