Answer:
The data item is 
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Mean of 400 and a standard deviation of 60.
This means that 
z=3
We have to find X when Z = 3. So




The data item is 
Hey there! :D
Let's find what Cheyenne runs in 10 minutes.
Divide 5.6 by 4.
5.6/4= 1.4
Multiply that by 6. (there are 60 minutes in an hour)
1.4*6= 8.4
"B" is the answer.
I hope this helps!
~kaikers
B, 8 to 11 because general number of marbles is 8+3=11 and only 8 of all are white)