Lu can type 140 words in 5 minutes, and Ray can type 140 words in 4 minutes. How many more words can Ray type?

Which of the following is the result of expanding the series

Look at this pattern ; 1,4,9, number 10000 belongs in this pattern . what’s the place of this number?

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?