If the population of a town was 20,000 in 1997 and 16,000 in 2007, what was the percent decline in the town's population?

The height of a flare fired from the deck of a ship in distress can be modeled by h(t)= -2(8t^2-52t-28), where h is the height of the flare above water and t is the time in seconds. a. find the time it takes the flare to hit the water.

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What are two numbers that have a sum of 15?