Alternatively, you could have an Intelligence of 9 and a Science skill of 76%.
Get the deliver Jet quest from Troy (if you want to do both Jet quests)
Talk to Myron in the Stables about Jet addiction and ask him about a cure for Jet. Convince him there might be a cure. Now, go to Vault City and talk to Dr. Troy.
After you first talk to Myron, you will get 2000 XP. After you talk to Dr. Troy about endorphin blockers, you will get 2000 XP and 2 Jet antidotes.
If you want to complete both this quest and Deliver a sample of jet to Dr. Troy., you must first get that quest. Next, talk to Myron about Jet production (not the cure) and have him join you. Then deliver the Jet sample to Dr. Troy, and immediately talk to Myron about a cure and finally talk to Dr. Troy about endorphin blockers.