Guess the correlation coefficient, r.

It would most likely be 0.9.

Step-by-step explanation:

The correlation coefficient ranges from -1 to 1 and is dependent on how strong the correlation is between the points. It cannot be 1.2 as it is above one and it cannot be 1 because all the points do not line up on the line of best fit. However, most do, so we can assume that there a strong positive linear relationship which means 0.9 would be the correct answer. The close r gets to zero means the less of a correlation there is. The line of best fit isn't negative so it cannot be -0.23 and it has a strongly positive correlation, not a weak one so it isn't 0.13.

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.