Acircle has a circumfrence of 14mm. find its area. give an exact answer

15.597 mm^2

Step-by-step explanation:

The formula for circumference of a circle 2πr, in which r is the circle's radius.

The formula for area of a circle π. This means that we can find the radius from the circle's circumference and use it to find the area.

First we have to equal 14 to 2πr because both are representations of circumference and we need to find r.

14 = 2πr

Solve:

14/2 = 2πr/2

7 = πr

7/π = πr/π

2.23 = r

Plug 2.23 into the formula for area as r and solve:

π(2.23)^2

π4.96

15.597

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.