Problem 12-30 (Algorithmic) (LO. 3) Archie runs a small mineral exploration business (as a sole proprietorship). In 2019, he purchased land (for $76,000) where he suspected a magnesium deposit was located. He incurred $18,000 of exploration costs related to the development of the magnesium mine in 2019 and an additional $24,000 of exploration costs in 2020. Archie elected to deduct these expenditures for regular tax purposes in both 2019 and 2020. In 2021, given a decline in magnesium prices, Archie chose to sell the property for $70,000, rather than bring the mine to production. What AMT adjustments are required in 2021 related to mine exploration expenditures and the sale of the land? negative As a result, in 2021 a s expenditures and a $ AMT adjustment is required for mine exploration AMT adjustment for the sale of the land. negative