An article reported that for a sample of 58 kitchens with gas cooking appliances monitored during a one-week period, the sample mean co2 level (ppm) was 654.16, and the sample standard deviation was 165.4.

(a) calculate and interpret a 95% (two-sided) confidence interval for true average co2 level in the population of all homes from which the sample was selected. (round your answers to two decimal places.) , ppm interpret the resulting interval. we are 95% confident that the true population mean lies below this interval. we are 95% confident that this interval does not contain the true population mean. we are 95% confident that this interval contains the true population mean. we are 95% confident that the true population mean lies above this interval.
(b) suppose the investigators had made a rough guess of 184 for the value of s before collecting data. what sample size would be necessary to obtain an interval width of 47 ppm for a confidence level of 95%?

Kai walked one and two-thirds of a mile on saturday and four and one-sixth of a mile on sunday. how many miles did kai walk?

Solve each quadratic equation by factoring and using the zero product property. [tex]x^2+6x+8=0[/tex]

In a test for esp (extrasensory perception), the experimenter looks at cards that are hidden from the subject. each card contains either a star, a circle, a wave, a cross or a square.(five shapes) as the experimenter looks at each of 20 cards in turn, the subject names the shape on the card. when the esp study described above discovers a subject whose performance appears to be better than guessing, the study continues at greater length. the experimenter looks at many cards bearing one of five shapes (star, square, circle, wave, and cross) in an order determined by random numbers. the subject cannot see the experimenter as he looks at each card in turn, in order to avoid any possible nonverbal clues. the answers of a subject who does not have esp should be independent observations, each with probability 1/5 of success. we record 1000 attempts. which of the following assumptions must be met in order to solve this problem? it's reasonable to assume normality 0.8(1000), 0.2(1000)%30 approximately normal 0.8(1000), 0.2(1000)% 10 approximately normal srs it is reasonable to assume the total number of cards is over 10,000 it is reasonable to assume the total number of cards is over 1000