A West Coast university statistics professor wishes to determine which surfboard brand delivers consistently longer rides, Channel Island or JS. He recruits two of his students who surf to assist in an experiment, and the student assigned to the Channel Island board is determined by coin flip. The three head out to the beach for an afternoon, with the professor holding up a sign at random times for the respective student to catch the next wave on his board, and the time spent on that wave is recorded. This is repeated until each student has ridden 10 waves. The brand of surfboard in this story is A) the explanatory variable. B) a parameter. C) stratified. D) the response variable. E) blinded.

This is repeated until each student has ridden 10 waves. The brand of surfboard in this story is "the explanatory variable"

Step-by-step explanation:

the explanatory variable otherwise known as the the Independent variable.

in the scenario above the brand of surfboard is independent of the event because the brand doesn't matter in the experiment.

i am sorry it just submitted an answer but the answer is 365 boys. hopes this

step-by-step explanation:

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: