If ∠P and ∠R are given, as well as the value of p, then explain whether the Law of Sines or the Law of Cosines should be used to solve for r.

Law of Cosines, because two sides and the included angle are known
Law of Cosines, because all sides are known
Law of Sines, because two angles and an opposite side are known
Law of Sines, because two sides and an opposite angle are known