A range of possible reconciliations have been proposed, including leaky layering at 660 km, layering deeper in the mantle, or ubiquitous compositional heterogeneity like a 'plum pudding'.

What are the different food types? What types of food are good for our health? Where does our food comes from? How do I get ready to cook? What tools do I use to prepare food? THE GREAT SPOON ...