Answer-
The measure of arc QR is 104°
Solution-
The Central Angle Theorem-
It states that the measure of inscribed angle is always half the measure of the central angle.
Inscribed angle is the angle formed in the interior of a circle when two secant lines intersect on the circle.
A central angle is the angle that forms when two radii meet at the center of a circle.
Here,
∠QTR = Central angle
∠QSR = Inscribed angle = 52°
Applying the theorem,
m∠QTR = 2×m∠QSR = 2×52°=104°