Find the expression for the electric field, e [infinity] , of the ring as the point p becomes very far from the ring ( x ≫ r ) in terms of the radius r , the distance x , the total charge on the ring q , and the constant k = 1 / ( 4 π ϵ 0 ).

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?

Which of the following circles have their centers in the third quadrant?

Me i’m stuck on all these questions besides the two bottom ones