Final answer:
The time of sunrise at 117.30' W is approximately 5:40 am, 30 minutes earlier than 6:10 am at 120.00' W.
Step-by-step explanation:
The time of sunrise is determined by the position of the Sun in relation to the observer's location on Earth. As you move westward, the time of sunrise becomes earlier. To determine the time of sunrise at 117.30' W, we need to consider the time difference between 120.00' W and 117.30' W.
- At 15° of longitude, the time difference is 1 hour.
- 120.00' W is 7.5° west of 105° W (117.30' W), so the time difference would be approximately 30 minutes.
Therefore, the time of sunrise at 117.30' W would be approximately 5:40 am (b) 6:05 am), 30 minutes earlier than 6:10 am at 120.00' W.