Exercise 1: A can buy copper from the market at the price of 1.695 USD/ton and sell it to B at the price of 1.750 USD/ton. B must accept it, and A will make a profit of 50 USD (1.750-1.
Exercise 2: Put the option. A can sell put options for $55. A makes a profit of $50 (55-5).
If the copper futures price rises, A will give up this right and lose $5, while B will get $5.
From the above example, we can draw the following conclusions:
First, as a buyer of options (whether call options or put options), there are only rights but no obligations. His risk is limited (the biggest loss is royalties), but theoretically his profit is unlimited.
Second, as a seller of options (whether call options or put options), he has only obligations and no rights. Theoretically, his risks are infinite, but his income is obviously limited (the biggest income is royalties).
People who buy put options have the right to sell the subject matter; People who sell put options are obliged to buy the subject matter.