A new model explaining this mysterious process suggests the core was created as dribs and drabs of iron percolated inward from Earth's lower mantle, according to a study published Oct. 6 in the journal Nature Geoscience. The mantle is the viscous, rocky layer between the crust and Earth's iron core.
Definition of flash card. : a card bearing words, numbers, or pictures that is briefly displayed (as by a teacher to a class) usually as a learning aid.
1 Bingo (United Kingdom), a game using a printed ticket of 15 numbers on three lines; most commonly played in the UK. 2  Bingo (U.S.), a game using a printed ticket of randomly generated 5x5 grid of numbers; most commonly played in the USA and Canada.  Bingo (card game), named by analogy to the game Bingo.