A sample of a radioactive isotope had an initial mass of 440 mg in the year 1990 and decays exponentially over time. A measurement in the year 1998 found that the
sample's mass had decayed to 40 mg. What would be the expected mass of the
sample in the year 2001, to the nearest whole number?

Rai compares two cable plans from different companies. which equation gives the correct value of mm, the number of months for which plans a and b cost the same?

The rate of decay of a radioactive substance depends upon the amount present initially. the mass y (mg) of the radioactive substance cobalt-60 present in a sample at time t (years) is represented by the exponential equation y=50e −0.1315 t . answer the following questions in complete sentences. 1. how does the exponential equation above compare to the equation for simple interest that is compounded continuously? explain the similarities. 2. what is the initial amount of cobalt-60 in the sample? 2. how much cobalt-60 is left after 8.4 years? show your work. 3. what would be the y-intercept of the graph? what does it represent? 4. after how many years will the amount of cobalt-60 left be 6.25 mg? explain what happens to the cobalt-60 after 50 years? 5. discuss some “real-world” examples and uses of cobalt-60

Side xy of triangle xyz is extended to point w, creating a linear pair with ∠wyz and ∠xyz. measure of an exterior angle what is the value of x? 64 80 100 180