Tiles numbered 1-25 are placed in a box. two tiles are selected randomly (not at the same time. one after the other) find the probability of drawing: drawing 10, replacing the tile and then drawing a multiple of 3

Find the value of the cosine for angle a

What is this inequality notation? t is less then or equal to 2

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?