To measure the distance across the river, Jonathan placed a rock on the opposite river bank. He walks 150 fr along the river bank and places a stake. Jonathan continues to talk another 120 ft along the river bank until he see the rock and the stake in the same line. If he walks out 36 ft from the river bank, how wide is the river?

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?