Which isotope has the longest half-life?

What are four key elements of the study of economics?

Food provides molecules that serve as fuel and building material for all organisms. plants undergo photosynthesis and make their own food. other organisms, like us and the horse seen above, are consumers and eat food. how do all organisms use food as fuel? be sure to include the name of the process in your answer. me.

This rapid change in species that rarely leaves behind fossil evidence is referred to as