Why did the crew of the zong ship throw some captive africans overboard?

they threw them overboard because they were too stubborn for example: the slave traders yell to row the boat but they're either tired or to weak to row and since they're either tired or weak they don't row as fast or as much and then the slave trader gets really mad causing him to throw the captives overboard to teach the others a lesson. or he'd throw them over to send someone else a message but #1 was a better example

demand is the need and oportunity to buy a given good or service.