Select all that apply. Which of the following are proportions?

3/4 = 15/20
2/8 = 3/12
3/4 = 8/10
25/10 = 5/2

Which statement justifies why angle ebc measures 90?

Given ab and cb are tangents of p, and m =10°. what is the measure of abp?

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?