Step-by-step explanation:
De qué forma how is your night give me a picture
To get your answer:
9 times 5 times two= 90
9 times 7.5 times two= 135
5 times 7.5 times two= 75
then add all of them together and you will get the surface area
90+135+75=300
you should have an answer of 300 feet²
We have the frequencies for each of the grades. We can estimate the number of students graded by adding all those frequencies. Let's call N the total number of grades:

We have then a total number of grades of 39.
The corresponding relative frequency for a grade is the ratio of the frequency to the total number of "samples", 39 in this case.
Then, for grade A, the relative frequency (RF) will be:

This will be the fraction of the total grades that are A. Represented as a percentage will be 10.26%, rounded to two decimal places.
Now, to complete the table we do the same for the other frequencies:
For grade B:

For grade C:

For grade D:

For grade F:
21 of your taking about area