Aprofessor would like to estimate the average number of hours his students spend studying for his class. he wants to estimate μwith 99% confidence and with a margin of error of at most 2 hours. from past experience he knows the standard deviation of number of hours spent studying to be 8 hours. how many students need to be surveyed to meet these requirements? a. 106b. 105c. 107d. 108

The appalachian trail is a hiking trail that passes through the appalachian mountains. three members of a teen hiking group hiked a section of the trail. the hikers stopped at a rest area and equally shared 3 4 gallon of water. how much water did each person get?

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.

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