Main street and washington avenue meet at a right angle. a large park begins at this corner. joe's school lies at the opposite corner of the park. usually joe walks 6.0 miles along main street and then 2.5 miles up washington avenue to get to school. today he walked in a straight path across the park and returned home along the same path. what is the difference in distance between the two round trips?

In a test for esp (extrasensory perception), a subject is told that cards only the experimenter can see contain either a star, a circle, a wave, or a square. as the experimenter looks at each of 20 cards in turn, the subject names the shape on the card. a subject who is just guessing has probability 0.25 of guessing correctly on each card. a. the count of correct guesses in 20 cards has a binomial distribution. what are n and p? b. what is the mean number of correct guesses in 20 cards for subjects who are just guessing? c. what is the probability of exactly 5 correct guesses in 20 cards if a subject is just guessing?