n January 2018, Ace Mining Corporation purchased a mineral mine for $4,200,000 with removable ore estimated by geological surveys at 2,500,000 tons. The property has an estimated (salvage) value of $400,000 after the ore has been extracted. Ace incurred $1,150,000 of development costs preparing the property for the extraction of ore. During 2018, 340,000 tons were removed and sold. For the year ended December 31, 2018 Ace should record what amount of depletion?

		$516,800
		$594,000
		$456,000
		$673,200

ABC Co. uses the units-of-production method for computing depreciation on its only plant asset. The credit to accumulated depreciation from period to period during the life of the asset will

		vary with production.
		vary with unit sales.
		be constant.
		vary with sales revenue.