im assuming its 12 i) i let angle APQ = x , angle ATQ = x , APQ = ATQ = x (angles subtended by same arc are equal)
angle AQT = 90 (angle in semi circle)
therefore angle TQC = 90 , (angle sum of st line)
angle QTC = 180 - (90 + x) = 90 - x (angle sum of st line)
therefore angle QCT = 180 - 90...