Hich region of the united states experienced the greatest decrease in population by percentage from 2000 to 2004?

Well, a and b together would be negative. b alone would also be negative.

If a particular resource is not useful or needed then the price would be considerably low. once that resource is needed the price or value will raise depending on how useful or needed it is especially if the resource is low in quantity, the consumers would pay whatever they have to, to get that material.