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5.4 The following table gives the length of the life (in hours) of 400 TV picture tubes: Length of Life No. of Length of Life No. of (in hours) Picture Tubes (in hours) Picture Tubes 4000 - 4199 12 5000 - 5199 55 4200 - 4399 5200 -5399 36 4400 - 4599 65 5400 - 5599 25 4600 -4799 78 5600- 5799 9 4800 -4999 90 Compute the mean, standard deviation, and coefficient of skewness