The amount of time spent updating websites for small businesses averages 50 minutes per week with a standard deviation of 10 minutes per week. if we consider the distribution of times as mound-shaped and symmetric, use the standard deviation to explain where we would expect "most" of the times will fall each week?
a) Way too long
b) Between 30 and 70 minutes
c) Between 40 and 60 minutes
d) Between 20 and 80 minutes