A worker at the local Department of Motor Vehicles (DMV) claims that 60% of teenagers smile in their driver’s license photo. In a random sample of 10 teenagers from last month’s new driver’s licenses, only 4 of them were smiling in their photos. To see how unusual this sample is, 100 simulated trials were conducted under the assumption that 60% of teenagers smile for their driver’s license photo. Based on the dotplot of the simulation results and the random sample from last month’s new driver’s licenses, which conclusion can be drawn?

A) The actual proportion of teenagers who do not smile is only 8%.
B) It is clear that exactly 6 out of 10 teenagers will smile in their driver’s license photo.
C) If we continued to take more samples of 10 teenagers, the center of the distribution would shift to 6.
D) There is about an 8% chance that 4 or fewer teenagers smiled for their photo. This is not unusual and is not convincing evidence that the true probability is less than 60%.

the results from a pre-test for students for the year 2000 and the year 2010 are illustrated in the box plot. what do these results tell us about how students performed on the 29 question pre-test for the two years?

if we compare only the lowest and highest scores between the two years, we might conclude that the students in 2010 did better than the students in 2010. this conclusion seems to follow since the lowest score of 8 in 2010 is greater in value than the lowest score of 6 in 2000. also, the highest score of 28 in 2010 is greater in value than the highest score of 27 in 2000.

but the box portion of the illustration gives us more detailed information. the middle bar in each box shows us that the median score of 20 in 2000 is greater in value than the median score of 17 in 2010. further, we note that the box and whiskers divide the illustration into four pieces. each of these four pieces represents the same portion of students. so, the upper half of the students in 2000 scored in the same score range as the upper one-fourth of the students in 2010, see the illustration at a score of 20.

by considering the upper one-fourth, upper half, and upper three-fourths instead of just the lowest and highest scores, we would conclude that the students as a whole did much better in 2000 than in 2010. we would conclude that as a whole the students in 2010 are less prepared than the students in 2000.

in this section, we discuss box-and-whisker plots and the five key values used in constructing a box-and-whisker plot. the key values are called a five-number summary, which consists of the minimum, first quartile, median, third quartile, and maximum.

step-by-step explanation:

the answer is b.

64

step-by-step explanation:

c=2πr=2·π·8≈64

a sample of water is taken and kept in a beaker in a freezer at a constant temperature of 0°c. if the system is at dynamic equilibrium, which of these statements is true?