1.1> The weekly incomes of shifts supervisors in the glass industry are normally distributed with a mean of $1000 and a standard deviation of $100. What is the probability of selecting a shift supervisor in the glass industry whose income is: a.- Between $790 and $1000? b.- Less than $790? 1.2: The employees of Cartwright Manufacturing are awarded efficiency ratings. The distribution of the ratings follows a normal distribution. The mean is 400, the standard deviation is 50. a.- What is the area under the normal curve between 400 and 482? b.- What is the area under the normal curve for ratings greater than 482