Can someone please tell me the answers but also explain how to do it? Thank you

8: 90 degrees, 9: 165 degrees, 6: 81 degrees, 7: angles in the same segment are equal

Step-by-step explanation:

For question 8:

Notice how the line AB just barely touches the edge of the circle. We call this kind of line a tangent. The point O is at the center of the circle so the line OB is a radius. The angle between a tangent and a radius is always 90 degrees, so ABO is 90 degrees.

For question 9:

By the exact same logic as 8, ACO is also 90 degrees. The sum of interior angles in a 4 sided shape (a quadrilateral) is always 360 degrees. This means that 15 + 90 + 90 + x = 360 = 195 + x so x = 360 - 195 = 165

For question 6/7:

We use the theorem that the angles in the same segment are equal. This means that a is 81 degrees.

it would be:

c.parallelogram.

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.