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4. Newfoundland & Labrador is known for its winter storms. In one winter, there were 29 storms in which there was measurable snow accumulation. The snowfall accumulation is given below. Accumulation (in cm) # of Winter Storms 0 to under 10 cm 10 to under 20 cm 11 20 to under 30 cm 5 30 to under 40 cm 40 to under 50 cm Calculate the mean Accumulation of the winter storms and the standard deviation of this Frequency Distribution (ie. Grouped Data)