statistics mathematical problems

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Can anyone provide the solutions to these problems? 1.The mean and standard deviation of the gross weekly income distribution of a local company's 150 employees were determined to be $170 and $10 respectively. Approximately what percentage of the employees would be expected to have incomes over $190 per week? Under $160 per week? If you were employed by this company and your weekly income was $185, how many standard deviations would your salary be away from the mean salary? What would your Z-score then be? 2. A company that bottles soda has determined that it lost an average of 30.4 cases per week last year due to breakage in transit. The standard deviation of the number of cases lost per week was 3.8 cases. With only this information, what can you say about the number of weeks last year that the company lost more than 38 cases due to breakage in transit? Justify your answer. 3. The tread life of a particular brand of tire is a random variable best described by a normal distribution with a mean of 60,000 miles and a standard deviation of 8,300 miles. If the manufacturer warrants the tires for the first 45,000 miles, what proportion of the tires will be replaced under warranty? What if the warranty is for the first 40,000 miles? 4. Salaries for a Computer tech company for 2006 are listed below: 7.88M, 7.70M, 4.20M,6.6M, 6.19M, 920K 5.37M, 1.35M, 870K, 760K, 950K, 4.16M 2.65M, 1.97M, 5.22M, 720K, 1.61M, 720K 3.55M, 1.65M, 1.58M, 810K, 850K, 470K 600K, 590K, 340K, 510K, 470K, 850K 400K, 600k, 390k, 450k, 370k, 1.66M 280k, 950k, 990k, 720k, 1.30m, 410k 580k, 300k, 300k,. 440k, 270k, 540k 960k, 460k, 290k a. Display the frequency distribution of the salaries graphically in a histogram (choose intervals to use along the horizontal axis) and tell what is the mean, median and skew of the distribution.