hope I'm right but either 2 or 4 i can kinda go either way
<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.
70-3·6+9
Remember PEMDAS.
You must multiply the 3 and 6 together, and you would get 18.
Then, you subtract 18 from 70, which would give you 52.
And finally, you would add 9 to 52, getting 61 as your final answer.
<span>7x^2 + 7y^2 - 28x + 42y - 35 = 0.
⇒ </span><span>x^2 + y^2 - 4x + 6y - 5 = 0.
⇒ (x-2)^2 + (y+3)^2 = 18
1. B
2. C
3. B
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