Answer:
See below.
Explanation:
Part A:
triangle QPR and triangle PSR are similar
Part B:
Triangle QPR is a right triangle with right angle QPR.
Triangle SPR is a right triangle with right angle PSR.
Angle QPR of triangle QPR corresponds to and is congruent to angle PSR of triangle PSR.
Angle R of triangle QSR corresponds to and is congruent to angle R of triangle PSR.
The similar triangles by AA Similarity are
triangle QPR and triangle PSR
Part C:
QR/PR = PR/SR
16/PR = PR/4
PR² = 16 * 4
PR² = 64
PR = 8