Denise and Donna want to exchange secrets from across a crowded whispering gallery. Recall that a whispering gallery is a room which, in cross section, is half of an ellipse. If the room is 30 feet high at the center and 90 feet wide at the floor, how far from the outer wall should each of them stand so that they will be positioned at the foci of the ellipse? Fill in the blank: Denise and Donna should each stand ft from the outer wall so that they will be positioned at the foci of the ellipse. Round your answer to the nearest whole ft (no decimal places).

Find the area of a trapezoid with bases 14 cm and 18 cm and height 10 cm. 160 cm2 140 cm2 180 cm2 126 cm2

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.

Which expression is equivalent to sq-80