Answer:
The calculation in step 3 is wrong
Step-by-step explanation:
1) The mean of a dataset is given by the sum of the values of the dataset divided by the number of values.
In this problem, the dataset is
35, 16, 23, 42, 19
And the number of data is
N = 5
So the mean is

So, step 1 is correct.
2)
The absolute deviation of a value in the dataset is the absolute value of its difference from the mean value:

Since here the mean value is

Then for each of the values in this dataset, we have:

So calculations in step 2 are also correct.
3)
The mean absolute deviation is given by the sum of the absolute deviations for each data divided by the number of values in the dataset.
Therefore in this problem, it is:

While the result reported by Dora is 9.5: therefore, this step is not correct.
Answer:
7
Step-by-step explanation:
Since the order of the students selected is important in this item, the concept used for this question is that of the permutation. For this item it is the "permutation of 28 taken 6". This may be mathematically expressed as 28P6. The numerical answer is 271252800. Thus, the answer is letter C.
Answer: 
<u>Step-by-step explanation:</u>
The power rule is "multiply the exponents".
You must understand that the exponent of both h and g is 1.
Multiply 1 times 9 for both variables.
