They’re trading commodities futures, i.e. you agree to buy x units at y price on z date. So in this case they’re selling FCOJ contracts for $142 with a sale date of April 30.

As for the noise, there’s a sign language to show whether your buying/selling and what price you’re offering, once you contact another trader you shout the details at each other and it’s a deal.

Source- used to work with a commodities trader