Green Corporation, a calendar year taxpayer, has ordinary income of $10,000 and a long-term capital loss of $12,000 in 2021. Green incurred a long-term capital gain of $2,500 in 2018 and a long-term capital gain of $5,000 in 2020. 

a. How much of the long-term capital loss can be deducted in 2021?

b. Carried back to prior years?

c. Carried forward to future years?

d. What is the nature (long- or short-term) of any carrybacks or carryforwards?