A researcher asked five of his doctor friends if they thought the new Brand X medicine that he developed was effective. Four responded "yes." The researcher used the results to write a TV
advertisement claiming that "4 out of 5 doctors prefer Brand X medicine." Is this a valid inference?
Explain.
Use pencil and paper. Explain all of the factors that are necessary for an inference to be valid.
Is the inference valid? Explain. Choose the correct answer below.
OA. No, because the doctors asked are not a representative sample of the population of doctors.
OB. No, because 4 doctors said yes out of 9 who were asked.
OC. Yes, because 4 doctors said yes out of 5 who were asked.
OD. Yes, because the doctors asked are a representative sample of the population of doctors.

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

List the sides of δrst in in ascending order (shortest to longest) if: m∠r =x+28°, m∠s = 2x+16°, and m∠t = x+12°

An octagonal prism has jow many lateral faces?