Triangle PQR with side p across from angle P, side q across from angle Q, and side r across from angle R
 HELP PLEASE I COULDN'T FIND THE ANSWER ANYWHERE
If ∠R measures 18°, q equals 9.5, and p equals 6.0, then which length can be found using the Law of Cosines?
 1. p
 2. q
 3. RQ
 4. PQ