Select all that apply. to solve an equation with a variable, which of the follow are done? inverse operations are used addition is always used the variable needs to be isolated the value of the variable should be guessed first

When you answer this can you explain

What are the coordinates of the midpoint of ab? ,1/2) /2,-1) ,-3/2) /2,-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?