Suppose that the raw daily oxygen purities de- livered by an air-products supplier have a stan- dard deviation σ ≈ .1 (percent), and it is plausi- ble to think of daily purities as independent ran- dom variables. approximate the probability that the sample mean x of n = 25 delivered purities falls within .03 (percent) of the raw daily purity mean, μ.

Fran would like to estimate the mean amount of time it takes people in her town to travel to work. the town's population is 150,000 and about 90,000 of those are working adults. which statements are true? select each correct answer. there is no way to infer the value of the mean. she must collect data for all 90,000 working adults and calculate the mean. a larger sample of working adults will provide a better estimate of the true mean than a smaller sample. the population of working adults is too large for using a sample to estimate the mean of the entire group. if she takes a random sample of the population of working adults in her town, the mean for that group is likely close to the mean for the entire group.

We must first determine the shape of a rectangular prisms _ a0 to find area of the prism

Amountain climber starts a climb at an elevation of 453 feet above sea level at his first rest stop he has climbed 162 feet and by his second rest stop he has climbed another 207 feet its getting late in the day so the climber starts his way down if the climber desends 285 feet how much does he need to ascend or descend to return to the original starting point