Answer:
305.6 seconds
Explanation:
To calculate how much longer it will take light to travel to Earth than to Mercury, we can use the formula for time:

Sun to Mercury
First, calculate the time it takes for light to travel from the Sun to Mercury.
Given:
- Distance: d = 5.792 × 10⁷ km
- Speed: s = 300,000 km/sec
Substitute the given values into the formula:

Therefore, the approximate time it takes for light to travel from the sun to Mercury is 193.07 seconds (2 d.p.).
Sun to Earth
Now, calculate the time it takes for light to travel from the Sun to Earth:
Given:
- Distance: d = 1.496 × 10⁸ km
- Speed: s = 300,000 km/sec
Substitute the given values into the formula:

Therefore, the approximate time it takes for light to travel from the sun to Earth is 498.67 seconds (2 d.p.).
Difference
To find out how much longer it takes light to travel to Earth than to Mercury, subtract the time to Mercury from the time to Earth:

So, it will take approximately 305.6 seconds longer for light to travel from the Sun to Earth than to Mercury.

Additional Information
As one calculation:
