The ocean floor is growing by 8 centimeters every five years. What is the speed of the ocean floor's growth?

Answer: At spreading rates of about 15 cm (6 inches) per year, the entire crust beneath the Pacific Ocean (about 15,000 km [9,300 miles] wide) could be produced in 100 million years. For currents it can reach as high as 250 cm/sec (98 in/sec, or 5.6 mph