In triangle pqr, r2 = p2 + q2.

which equation is true about the measure of the angles of the triangle?

the measure of angle prq is equal to 100 degrees
the measure of angle prq is equal to 90 degrees
the measure of angle pqr plus the measure of angle qpr is equal to 80 degrees
the measure of angle pqr plus the measure of angle qpr is equal to 70 degrees