Answer:
C
Step-by-step explanation:
You are choosing 3 from a total of 12. Order does not matter. So you are working with combinations. The answer symbolically is
12C3
12C3 = 12!/(9!3!)
12C3 = 12 * 11 * 10 * 9!/(9! 3!)
12C3 = 12 * 11 * 10/6
12C3 = 2 * 11 * 10
12C3 = 220
Answer:
you need 100ml of 5X TAE and 400ml of water.
Step-by-step explanation:
You need to use a rule of three:

where:

and

Therefore:


Then just rest the TAE volume to the final Volume and you get the amount of water that you need to reduce the concentration.
Using the normal distribution, it is found that there are 68 students with scores between 72 and 82.
<h3>Normal Probability Distribution</h3>
The z-score of a measure X of a normally distributed variable with mean
and standard deviation
is given by:

- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
In this problem, the mean and the standard deviation are given, respectively, by:

The proportion of students with scores between 72 and 82 is the <u>p-value of Z when X = 82 subtracted by the p-value of Z when X = 72</u>.
X = 82:


Z = 1
Z = 1 has a p-value of 0.84.
X = 72:


Z = 0
Z = 0 has a p-value of 0.5.
0.84 - 0.5 = 0.34.
Out of 200 students, the number is given by:
0.34 x 200 = 68 students with scores between 72 and 82.
More can be learned about the normal distribution at brainly.com/question/24663213
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Changing the subject of the formula
You took a picture of the ground this doesn't help at all. Take a picture of the book