The angle between the segment labled x and the chord labeled 30 is not specified. The measure of x cannot be determined, except to say that it is somewhere between 16 and the radius of the circle, √(16²+15²) = √481 ≈ 21.93.
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If the angle between x and the chord were marked as a right angle, one could say x=16, because all chords of the same length are the same distance from the center of the circle.
2560000 sequences of answers are possible.
<em><u>Explanation</u></em>
Total number of questions = 10
First 4 questions have 5 choices each and remaining (10-4)= 6 questions have 4 choices each.
So, the possible sequences of answers for first 4 questions 
and the possible sequences of answers for remaining 6 questions 
Thus, the total possible number of sequences of answers = (625 × 4096) = 2560000
It’s 0.09 or .09. Hope this helps:)