A secret code is designed by choosing a letter from the alphabet and then choosing a digit from 0 to 9. Which equation below correctly represents the probability of choosing the secret code "7Q?"
P(7UQ) = P(7) + P(Q)
P(7UQ) = P(7) P(Q)
P (7nQ) = P(7) + P(Q)
P(7nQ) = P(7) PQ)

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.

The surface area of the triangular prism is .

Rationalize the denominator- 12x/√x-10