Final answer:
The correct advice for Mr. Lewin is to self-administer pain medication every 30 minutes.
Step-by-step explanation:
The subject of this question is Health and the grade is High School.
Based on the question, Mr. Lewin needs to self-administer pain medication. To determine the frequency, we need to consider the medication's instructions or dosage guidelines. Since the options are given in minutes, let's assume we have the dosage interval in minutes. If the recommended dosage interval is 30 minutes, then the correct answer would be a) 30 minutes.