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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.

What effect would doubling all the dimensions of a triangular pyramid have on the volume of the pyramid? explain your reasoning.

(co 3) the soup produced by a company has a salt level that is normally distributed with a mean of 5.4 grams and a standard deviation of 0.3 grams. the company takes readings of every 10th bar off the production line. the reading points are 5.8, 5.9, 4.9, 6.5, 5.0, 4.9, 6.2, 5.1, 5.7, 6.1. is the process in control or out of control and why? it is out of control as two of these data points are more than 2 standard deviations from the mean it is in control as the data points more than 2 standard deviations from the mean are far apart it is out of control as one of these data points is more than 3 standard deviations from the mean it is in control as the values jump above and below the mean