PLEASE HELP! For a concert 5,000 tickets were sold, and the proceeds were $72,000. Tickets for children 16 and younger were $10, adults were $20, and seniors 60 and older were $15. There were 3 times more children than seniors at the concert. What system of equations represents the number of children, c, adults, a, and seniors, s, that attended the concert?

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 following hormone had their receptors in the cell membrane except a-insulin b-tsh c-gh d- cortisol

Which is a logical conclusion based on the given information? a. figure abcd is a rhombus by the definition of a rhombus. b. segment ac is congruent to segment dc by cpctc. c. angle acb is congruent to angle adc by the angle-side-angle theorem. d. triangle acd is congruent to triangle cab by the hypotenuse-leg theorem.