The correct option is (a).
Explanation
The longitudinal extent of India and the calculation of Indian Standard Time (IST). The Earth rotates 360° in 24 hours, which corresponds to 15° per hour or 1° every 4 minutes.Statement 1 is Correct:
India's longitudinal extent stretches from approximately 68°7' E in Gujarat to 97°25' E in Arunachal Pradesh. This span is roughly 30°. Since a 1° difference corresponds to a 4-minute time difference, 30° results in a time lag of approximately 120 minutes, or two hours, between the westernmost and easternmost points of the country.
Statement 2 is Incorrect:
While local solar time differs from place to place based on longitude, watches across India are set to a single time zone known as Indian Standard Time (IST). Therefore, watches show the same time everywhere in the country, irrespective of the local meridian.
Statement 3 is Incorrect:
The Standard Meridian of India is 82°30' E. This meridian passes through Mirzapur (near Prayagraj) in Uttar Pradesh, as well as through the states of Madhya Pradesh, Chhattisgarh, Odisha, and Andhra Pradesh. It does not pass through Mumbai, which is located at approximately 72° E.
Key Takeaway: India spans approximately 30° of longitude, creating a two-hour solar time difference between its extremities, but the entire country follows a single standard time based on the 82°30' E meridian.