Almost every year, there is some incidence of volcanic activity on the island of japan. in 2005 there were 5 volcaninc episodes, defined as either eruptions or sizable seismic activity. suppose the expected number of episodes is 2.4 per year. let x be the number of episodes in the 2-year period 2008-2009.
(a) what model might you use to model x? why ? justify the appropriateness of this model for this problem. provide the parameter values for the model chosen.
(b) using the model calculate the probability that there will be no episodes in this period?
(c) using the model, calculate the probability that there are more than three episodes in this period.

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

Evaluate the expression. (9 + 5)(3 + 2)0

It appears that people who are mildly obese are less active than leaner people. one study looked at the average number of minutes per day that people spend standing or walking. among mildly obese people, the mean number of minutes of daily activity (standing or walking) is approximately normally distributed with mean 376 minutes and standard deviation 64 minutes. the mean number of minutes of daily activity for lean people is approximately normally distributed with mean 528 minutes and standard deviation 107 minutes. a researcher records the minutes of activity for an srs of 7 mildly obese people and an srs of 7 lean people. use z-scores rounded to two decimal places to answer the following: what is the probability (image for it appears that people who are mildly obese are less active than leaner people. one study looked at the averag0.0001) that the mean number of minutes of daily activity of the 6 mildly obese people exceeds 420 minutes? what is the probability (image for it appears that people who are mildly obese are less active than leaner people. one study looked at the averag0.0001) that the mean number of minutes of daily activity of the 6 lean people exceeds 420 minutes?