A sample of a radioactive isotope had an initial mass of 480 mg in the year 2009 and decays exponentially over time. A measurement in the year 2011 found that the
sample's mass had decayed to 390 mg. What would be the expected mass of the
sample in the year 2016, to the nearest whole number?

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Yesterday i ran 5 miles. today, i ran 3.7 miles. did my percent increase, decrease or is it a percent error? plz i need

Three baby penguins and their father were sitting on an iceberg 0.50.50, point, 5 meters above the surface of the water. the father dove down 4.74.74, point, 7 meters from the iceberg into the water to catch dinner for his kids. what is the father penguin's position relative to the surface of the water?