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triangle pqr is transformed to triangle p'q'r'. triangle pqr has vertices p(4, 0), q(0, −4), and r(−8, −4). triangle p'q'r' has vertices p'(1, 0), q'(0, −1), and r'(−2, −1). plot triangles pqr and p'q'r' on your own coordinate grid.

part a:
what is the scale factor of the dilation that transforms triangle pqr to triangle p'q'r'? explain your answer.

part b:
write the coordinates of triangle p"q"r" obtained after p'q'r' is reflected about the y-axis.

part c:
are the two triangles pqr and p''q''r'' congruent? explain your answer.

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?