Find the value of y. A.
B. 6
C.
D.16

which agrees with answer A

Step-by-step explanation:

Notice there are three right angle triangles for which we can apply the Pythagorean theorem:

In the small triangle at the bottom we have the Pythagorean theorem rendering:

(a)

in the second right angle triangle on top of the previous one, if we call the vertical side on the right side "z", we have:

(b)

and finally in the large right angle triangle:

(c)

We can combine equations b and c to obtain:

and then combine this and (a) to get:

the infinity sign

step-by-step explanation:

introduction, methodology, results, discussion

step-by-step explanation:

an observational study is one which consists of actual observation to record data and then analyse the data.

there are a number of factors that should be analyzed before starting an observational study.

the main four factors are:

i) introduction:   this should be analysed to check whether the purpose of the study is correctly established and the data recorded are appropriate for the study

methodology:   the method of collecting the data, such as whether randomly selected, and whether sample size matches with the population to be studied, whether questions asked are easy to answer by common men, etc.

results: then results such as summary of data with comments should be studied thoroughly

discussion:   the last is the discussion, this can be either by management people or persons who are all interested , etc.