PO = RO (radius)
there for POR is an  isosceles triangle
RPO= 35
∠ORP+∠RPO+∠POR =180° (angle sum prop)
35°+35°+∠POR          =180°
               ∠POR          =180-70
∠POR+∠ROQ =180° (supplementary angles)
           ∠ROQ  =180-110

It is Diameter
Dont u Know???? Diameter is a Straight Line
i am not telling that. i do know that.
i am asking how can we determine that p, o and q are in a straight line when it is never told in the question nor it is shown in the figure.
nor it is said that poq is the diameter