Engineers must consider the breadths of male heads when designing helmets. The company researchers have determined that the population of potential clientele have head breadths that are normally distributed with a mean of 6.3-in and a standard deviation of 1.2-in. In what range would you expect to find the middle 50% of most head breadths? Between __________ and ____________ . If you were to draw samples of size 55 from this population, in what range would you expect to find the middle 50% of most averages for the breadths of male heads in the sample? Between ______________ and ______________.