The answer to the sentence is "$2500 of this gain is from collectibles" Where do you get that number from? Thanks! Please breakdown every calculation

Problem 3-49 (LO. 8) During 2021, Chester (a married taxpayer filing a joint return) had the following transactions involving capital assets: Gain on the sale of an arrowhead collection (acquired as an investment at different times but all pieces have been held for more than 1 year) Loss on the sale of IBM Corporation stock (purchased 11 months ago as an investment) Gain on the sale of a city lot (acquired 5 years ago as an investment) $6,000 (3.500) 2,000 a. Indicate the tax treatment for each item. Gain on the sale of an arrowhead collection Loss on the sale of IBM Corporation stock Gain on the sale of a city lot of . However, Overall, Chester has taxed at a maximum rate of of this gain is from collectibles, which are b. If Chester has taxable income (including the property transactions) of $378,400, what is the income tax regarding these transactions? He has a marginal tax rate of 32%. If Chester has taxable income (including the property transactions) of $74,125, what is the income tax regarding these transactions? He has a marginal tax rate of 12%