The grades on the last history exam had a mean of 80%. assume the population of grades on history exams is known to be distributed normally, with a standard deviation of 5%. using the empirical rule, approximately what percent of students earned a score between 70% and 80%?

a)3.5%
b)5%
c)47.5%
d)95%

At a constant it will take one hour to travel 32 mi.at that speed it will take 1/2 hr to travel the remaining 16 mi.it will take 1+1/2 hr to travel the 48mi @ 32mph.so 1 hr = 60 min& 1/2 hr = 30 min1+1/2 hr = 90 min.there are 60s in each 90 × 60 = 3600 seconds.the real question seriously is he why are they driving so slow? ! lol.

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