Jim wants to conduct a survey of u. s. teens aged 13 - 15 to find out what songs are their favorites. to do this, he does a random survey of 300 teens aged 12 - 15.

which of the following correctly describes his sample?
this method of sampling is neither biased nor unbiased.
this method of sampling is unbiased.
this method of sampling can be considered both biased and unbiased.
this method of sampling is biased.

David is spreading mulch on a triangular area of his flower bed. the coordinates of the vertices of the area are (1, 3), (9, 3), and (4, 6). what is the area of the triangle if each square has an area of 3 square feet?

When 142 is added to a number the result is 64 more times the number my options are 35 37 39 41

(b) suppose that consolidated power decides to use a level of significance of α = .05, and suppose a random sample of 100 temperature readings is obtained. if the sample mean of the 100 temperature readings is x⎯⎯ = 60.990, test h0 versus ha and determine whether the power plant should be shut down and the cooling system repaired. perform the hypothesis test by using a critical value and a p-value. assume σ = 5. (round your z to 2 decimal places and p-value to 4 decimal places.)