Answer:
.
Step-by-step explanation:
Answer:
2,436 students
Step-by-step explanation:
At a 90% confidence level, the z-score is 1.645 and the confidence interval is given by:

Where s is the standard deviation, and n is the sample size.
If they want the length of their confidence interval to be no greater than 0.2, it must be no further than 0.1 from the mean 'X':

Rounding up to the next whole number, the sample size should be 2,436 students.
Answer:
A
Step-by-step explanation:
i stands for square root of negative 1. If you multiple i and square root of 23 you will end up with the original
A. The expression has two factors.
The two factors of the expression 7(2x+5) are 7 and (2x+5).
Hope this helps.
So firstly, add both sides by 6: 
Next, multiply both sides by 4, and your answer will be 