They compared prices at Whole Foods stores in half a dozen cities to those at various competing supermarkets to determine which stores were cheaper. They found that Whole Foods is about 15% more expensive than other conventional supermarkets, such as Kroger, Wegmans, and Safeway.
A type of igneous rock. Basalt is the most common rock type in the earth's crust and makes up most of the ocean floor.
The oldest rocks on the ocean floor are 200 mya â very young when compared with the oldest continental rocks, which date from 3.8 billion years ago. In order to collect paleomagnetic data dating beyond 200 mya, scientists turn to magnetite-bearing samples on land to reconstruct the Earth's ancient field orientation.