1. The heights of 1567 Douglas fir trees were measured to have a mean of 126.8 ft and a standard deviation of 43.6 ft.
   
   
   1. Assuming this data is normal, determine the percent of trees that you would expect to be shorter than 24 ft.

   2. Assuming the data is normal, determine the percentage of trees you expect to be taller than 241 ft.

   3. The shortest and tallest trees measured were 24 ft and 241 ft. Based on the information provided, is it reasonable to treat this data as normal? Explain.
      
      
2. Suppose a set of data is normally distributed with a mean of 43 and a standard deviation of 12. Determine an upper limit and a lower limit that would encompass the middle 90% of the data.

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