I believe the answer to the first question is:
R is the midpoint of PQ. (I think)
The answer to the second question is:
Rectangle. Because rectangles are the only shape in that list that has parallel sides and congruent angles.
And the answer to the third question is:
16, 16, 18. Because an isosceles triangle is a triangle that has two sides of the same length.
I hope this helps! :)