Brainliest + 20 pts to whoever helps!

A simple random sample of 8 women basketball player's weights has a standard deviation of 7.5 lb. Find the test statistic, using a 0.05 significance level, to test a claim that the standard deviation of all weights of women basketball players is less than 9 lb.
a. 5.833
b. 10.080
c. 5.556
d. 4.861

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?