In our widget example, we will assume that the fixed cost for the stapler, pen, and âfactoryâ is $10 and the cost of each worker hired is $5 per worker. Since fixed costs are constant, the firm incurs $10 regardless of the level of output. Labor is the only variable cost computed by $5 times the number of workers.
How Bull Sharks Can Live in Both Ocean and Fresh Water. Although there are a handful of species that live in freshwater, we tend to think of sharks as being ocean dwellers. But there is also a very unique shark that can live in both ocean and fresh water estuaries and lakes: the Bull Shark.
Swimming Speed of the Average Shark. The general rule of thumb is that sharks can cruise at about 5 mph (8 kph), the speed of the fastest Olympic swimmer. If you're just a good swimmer, they have you beat. But often they are swimming around at a slower speed of about 1.5 mph (2.4 kph). But sharks can swim much faster when they are attacking, about 12 mph or 20 kph, the speed of a running human on land. You're not going to be able to swim away fast enough, you'd need a boat or jet ski or some other equipment.