Miguel helps Robin complete a homework project before heading to a harbor on the Hudson River. He and Kathy are worried that a houseboat may be sinking. A marine biologist tells them the difference between an estuary (like the Hudson) and a delta (like the Mississippi).In New Orleans, Kathy discovers the channels and levees that practically crisscross the area. Two ecologists inform her how important the Mississippi is to New Orleans, and how man and Nature must work together.Robin ventures to a region poisoned by acid rain, then labeled ""New York State's problem.""THE BLOODHOUND GANG: ""The Case of the Computer Caper, Part Two."" After a cold snap the night before, Vikki and Ricardo stake out the trash barrel in question. A strange lady pours water into the barrel a couple of minutes before Skip arrives with the money. Once the trash is dumped into a garbage truck, the order goes out: ""Tail it.""