Which of the following is an example of theoretical probability? a. wendy flipped a coin 5 times, and the results were 4 tails. the probability of tails is 4/5 . b. kenny rolled a number cube 9 times and got 4 even numbers. the probability of an even number is 4/9 . c. there are 52 playing cards in a deck, and 4 of them are aces. the probability of turning over an ace is 4/25 . d. there were 73 people in a grocery store, and 45 of them bought milk. the probability of people buying milk is 45/73 .

Jeffery conducted a survey in his school and found that 30 of the 50 eighth grade students' favorite subject is mathematics. based on the results, jeffery concluded that out of the 200 students in his school, 120 students' favorite subject is mathematics. select the statement that is true about jeffery's conclusion. a. jeffery's conclusion is not valid because the sample was biased since only 200 students were surveyed. b. jeffery's conclusion is valid because the sample was random since all of the students were eighth grade students. c. jeffery's conclusion is valid because the sample was random. d. jeffery's conclusion is not valid because the sample was biased since all of the students were eighth grade students.

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

Cone a has a surface area of 384 ft2 and cone b has a surface area of 96 ft? . what is the ratio of their volume?