A researcher is comparing stress levels in two groups working in different cities. If he decides to use an independent samples t-test, we may assume:. A) same participants were assigned to each group
B) the population variance is unknown
C) participants were observed many times
D) the data was not normally distributed

The radius of the circle is 4 cm and the measure of the central angle is 90° the area of the sector with a central angle measuring 90° and radius of length 4 cm is vt cm the triangle in the sector is 4 cm the area of the triangle is v/cm² the area of the segment of the circle is (471 - ) cm?

Suppose you just purchased a digital music player and have put 8 tracks on it. after listening to them you decide that you like 4 of the songs. with the random feature on your player, each of the 8 songs is played once in random order. find the probability that among the first two songs played (a) you like both of them. would this be unusual? (b) you like neither of them. (c) you like exactly one of them. (d) redo () if a song can be replayed before all 8 songs are played.

12.0 million metric tons of beef produced annually in the u.s. out if 65.1 mikkion metric tons of produced annually worldwide