A new test is developed to test for organic matter in soil samples, giving "positive" or "negative" results to indicate that a sample does or does not contain organic matter. For a soil sample that contains organic matter, the test will give a positive result 95% of the time and a negative result (false negative) 5% of the time. For a soil sample that does not contain organic matter, the test will give a positive result (false positive) 20% of the time and a negative result 80% of the time.

A study included a population of 1,000 soil samples, and 70% of those studied where known to contain organic matter.

Fill in the missing values in the table and statement below. If necessary, round the percentage to one decimal place.

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.