Yoshi is testing how being exposed to pictures of different types of foods affects sleepiness. He shows each participant five pictures of dessert, five pictures of entrees, and five pictures of salads, and then he measures sleepiness after each group of five pictures. To eliminate order effects, Yoshi creates all possible sequences for presenting the three types of food and all five pictures in each type. He then randomly assigns each participant to a sequence. What technique is Yoshi using to prevent order effects

(co 3) the times that customers spend in a book store are normally distributed with a mean of 39.5 minutes and a standard deviation of 9.4 minutes. a random sample of 25 customers has a mean of 36.1 minutes or less. would this outcome be considered unusual, so that the store should reconsider its displays? no, the probability of this outcome at 0.035, would be considered usual, so there is no problem yes, the probability of this outcome at 0.035, would be considered unusual, so the display should be redone no the probability of this outcome at 0.359 would be considered usual, so there is no problem yes, the probability of this outcome at 0.965 would be considered unusual, so the display should be redone