For certain ore samples, the proportion Y of impurities per sample is a random variable with density function f(y) = 9 2 y8 + y, 0 ≤ y ≤ 1, 0, elsewhere. The dollar value of each sample is W = 7 − 0.7Y. Find the mean and variance of W. (Round your answers to four decimal places.)

Saline iv fluid bags cost $64.20 for 24, 1000 ml bags from one supplier. another supplier sells 500 ml bags for $2 each. the hospital uses about 10,000, 1000 ml bags each month. nurses report that about half of the bags are more than half full when they are discarded. if you are going to use only one supplier, which would you choose and how much would you save with that choice? show calculator try it! if you buy 1000 ml bags, how many do you need to buy each month? type your answer in the space provided and click on the check answer button.

Two language majors, anna and megan, took exams in two languages. anna scored 85 on both exams. megan scored 74 on the first exam and 85 on the second exam. overall, student scores on the first exam had a mean of 82 and a standard deviation of 4, and the second exam scores had a mean of 71 and a standard deviation of 13. a) to qualify for language honors, a major must maintain at least an 85 average across all language courses taken. so far, which of anna and megan qualify? b) which student's overall performance was better?

Which situation can be modeled by the inequality 5 + 10w ≥ 45? a. you start with $5 and save $10 a week until you have at least $45. b.you start with 5 baseball cards and purchase 10 cards every week until you have at most 45 cards. c.you start with 5 water bottles and purchases cases of 10 water bottles each until you have a total of 45 water bottles. d.you spend $5 plus $10 per week until you have less than $45.