🔍 Key Concepts

• Standard time zones are generally 15 degrees of longitude wide • Zone numbers east and west of the Prime Meridian increase as you move away from 0° longitude • The dividing meridians between zones are usually on whole multiples of 15° of longitude

💭 Think About

• First, list the ideal central meridians for zones -2 and -3 based on 15° per zone. What longitudes do you get? • Once you know the central meridians, determine the halfway longitude between them. That halfway point is the dividing meridian. • Compare that halfway longitude to the answer choices and see which one matches most closely.

✅ Before You Answer

• Be sure you know whether negative zone numbers are east or west of Greenwich in the standard nautical time zone system. • Confirm that zones are centered on multiples of 15°, and their boundaries fall halfway (7°30') to either side. • Verify that your chosen longitude is exactly halfway between the central meridians for zones -2 and -3, not one of the central meridians themselves.