There are no longer any age limits on making contributions to traditional IRAs. The cap of age 70½ expired after 2019. This means that those of any age who continue to have earned income (or other income treated as earned income) can contribute to a traditional IRA for 2020 and later years. There was never any age cap on a Roth IRA.
Depreciable property used in a trade or business and held for more than a year. All Section 1231 gains and losses are netted; a net gain is treated as capital gain, a net loss as an ordinary loss.