Answer:7
Step-by-step explanation:
Hope this helps
<h2>
Answer with explanation:</h2>
Given : A standardized exam's scores are normally distributed.
Mean test score : 
Standard deviation : 
Let x be the random variable that represents the scores of students .
z-score : 
We know that generally , z-scores lower than -1.96 or higher than 1.96 are considered unusual .
For x= 1900

Since it lies between -1.96 and 1.96 , thus it is not unusual.
For x= 1240

Since it lies between -1.96 and 1.96 , thus it is not unusual.
For x= 2190

Since it is greater than 1.96 , thus it is unusual.
For x= 1240

Since it lies between -1.96 and 1.96 , thus it is not unusual.
Answer: 4y2z2 • (2x + y) • (4x2 - 2xy + y2) i think.hope it was helpful.
Step-by-step explanation:
Answer:
lets find how many books are in each box
120/5=24
so 24 book in a box so lets divide for the 216 books
216/24=9
9 boxes
Hope This Helps!!!
To determine whether a cause-effect relationship exists between two variables, a researcher must use an experimental approach.
<h3>What is
cause-effect relationship?</h3>
A cause-and-effect relationship is one which satisfies some conditions like:
- two events occur at the same time and in the same place
- one event immediately precedes the other
Therefore, To determine whether a cause-effect relationship exists between two variables, a researcher must use an experimental approach.
Learn more about cause-effect relationship on:
brainly.com/question/25680753
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