To get the volume of an object, one of the oldest techniques is to fill a container with water of which we know the volume (in this case 85mL), and drop the object in. The water will rise and show a new volume (225mL). If we subtract the old volume (85) from the new volume (225), we will get the volume of the object (225 - 85 = 140).
Answer: 0.31
Step-by-step explanation:
Let A denotes the event that the students report drinking alcohol and B denotes the students report using some type of tobacco product .
Given : P(A) =0.84 ; P(B)=0.33 and P(A∪B)=0.86
We know that 
Then, the probability that the student both drunk alcohol and used tobacco in the past month is given by :-

Hence, the probability that the student both drunk alcohol and used tobacco in the past month = 0.31
13 + -6.6=6.4 all I did was subtract 6.4 by 13 and I got 6.6 but then turned it negative to solve the equation