Question: Did this movie have any negative impact on director Joseph Sargent's life or career?
Question: How does Jake survive despite being seen eaten by the shark?
Answer: We never see Jake "eaten", he is merely shown being dragged underwater by the shark. Off screen, the shark simply let go of Jake and didn't kill him. In a movie full of factual errors and plot holes, this bit is actually somewhat realistic. Sharks typically do not eat humans, but will maul people on occasion and let go, presumably because they don't like the taste. How Jake survives underwater for minutes on end is not addressed. Originally, Jake was meant to be killed by the shark but for whatever reason, it was decided that Jake should survive and make a surprise appearance after the shark has been killed.
Question: How is the shark exactly killed?
Answer: When Bruce IV eats Mario Van Peebles, it also eats a device that they use to give it an electric shock by remote control. This makes it leap out of the water. The last time they do this, the long pole on the boat's bow impales it.
Question: At the of the movie Jake, Ellen, Hogie and somebody else are stuck in the middle of the ocean with no boat or no plane or nothing to get back home with. At the next scene they're back in safety. How?
Answer: Hogie radioed in before he crashed the plane into the sea. He gave them his location, told them to look for a boat called Neptune's Folly and send someone who can kill a shark.
Answer: When Ellen Brody took the boat to face the great white alone, her family feared for her safety and could have called Air/Sea Rescue. Also, even though it's not shown, Hogie could have radioed their location, when they found the boat or when the plane went down.
Answer: Not really, he went on to direct many films and TV shows/miniseries, earning some Primetime Emmys and Director's Guild Awards in the process.