The movement of the hard drive's read/write heads over different areas of the disk when accessing fragmented files is slower, compared to accessing the entire contents of a non-fragmented file sequentially without moving the read/write heads to seek other fragments.
The dorsal fins are small and at the base of the tail. The largest mantas can reach 1,350 kg (2,980 lb). In both species the width is approximately 2.2 times the length of the body; M. birostris reaches at least 7 m (23 ft) in width while M. alfredi reaches about 5.5 m (18 ft).
This creature has broad wings and a long tail. When these rays are born, they are. between 11 and 18 inches wide. They grow to be between 3 and 4 feet wide, from the. tip of one wing to the tip of another. Adults may weigh as much as 50 pounds or more. These rays are generally brown on top, with a white underside.