Answer:
Buyer 1: Exchange land.
Qualifies for §1031 deferral treatment. If Ross disposes of the land in exchange for another asset, he can differ the payment of capital gains taxes.
Buyer 2: Purchase land for cash.
If Ross sells the land for cash, then he will have a $50,000 long term capital gain which can be offset against a long term capital gain or a short term capital loss. In this case, Ross may want to sell the stocks in order to offset any taxes.
Buyer 3: Exchange stock.
The loss on the sale of stocks cannot be deferred (does not qualify for §1031 deferral treatment).
Buyer 4: Purchase stock for cash.
If Ross sells the stock for cash, he will be able to report the $50,000 short term capital loss, and he is able to offset the long term capital gain from selling the land.