A sample of a radioactive isotope had an initial måss of 690 mg in the year 1997 and decays exponentially over time. A measurement in the year 2001 found that the
sample's mass had decayed to 390 mg. What would be the expected mass of the
sample in the year 2011, to the nearest whole number

Find the area of the region that is inside r=3cos(theta) and outside r=2-cos(theta). sketch the curves.

You just purchased two coins at a price of $670 each. because one of the coins is more collectible, you believe that its value will increase at a rate of 7.1 percent per year, while you believe the second coin will only increase at 6.5 percent per year. if you are correct, how much more will the first coin be worth in 15 years?

Plz hurry finals a paper cup in the shape of an inverted cone is 8 inches tall and has a radius of 1.5 inches. how much water can the cup hold? use 3.14 for pi. round the answer to the nearest tenth. a) 12.6 cubic in. b) 18.8 cubic in. c) 37.7 cubic in. d) 56.5 cubic in.