In the last quarter of 2007, a group of 64 mutual funds had a mean return of 4.1% with a standard deviation of 6.9%. If a normal model can be used to model them, what percent of the funds would you expect to be in each region? Use the 68-95-99.7 rule to approximate the probabilities rather than using technology to find the values more precisely. Be sure to draw a picture first. a) Returns of negative 2.8% or less b) Returns of 4.1% or more c) Returns between negative 16.6% and 24.8% d) Returns of more than 17.9% a) The expected percentage of returns that are negative 2.8% or less is nothing%. (give an integer or a decimal.) b) The expected percentage of returns that are 4.1% or more is nothing%. (Type an integer or a decimal.) c) The expected percentage of returns that are between negative 16.6% and 24.8% is nothing%. (Type an integer or a decimal.) d) The expected percentage of returns that are 17.9% or more is nothing%. (Type an integer or a decimal.)

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