The complete solution is in image attached.
The sum of the measures of the angles of a polygon is given by (<em>n</em> - 2)(180), where <em>n</em> is the number of sides. In this case we would have (9-2)(180)=7(180)=1260. This is the <u>sum</u> of the angles. Since it is a regular nonagon, that means that all sides are congruent and all angles are congruent. Therefore we find the measure of each individual angle by dividing the sum, 1260, by the number of sides, 9. 1260/9=140. <em>x</em> forms a linear pair with one of the interior angles; that means that the interior angle, 140, added to <em>x</em> would give us 180. Therefore we find <em>x</em> by subtracting 180-140. <em>x</em> = 40.
The tangent of the given angles are the ratios <em>y</em> to the <em>x</em> coordinate of
the point of the terminal side on the unit circle.
The correct options are;
<h3>How to find the points on the unit circle</h3>
The tangent of an angle is given as follows;

First angle
An angle given is; 
Therefore;

The above result can be obtained as follows;

Which is obtained when we have;

Therefore
The required coordinates is therefore;
Second angle
The angle,
, gives; 
The above value can be obtained as follows;

Which gives;
Third angle
The angle 210° gives; tan(210°) =
, which can be obtained as follows;

Therefore;
Learn more about the unit circle here:
brainly.com/question/1673530