To find out how long it would take the spaceship to reach Mars, we can start with the given information about the distance to the moon and the travel time to get there:
- Distance to the Moon: 386,400 km
- Travel time to the Moon: 3 days
First, we can determine the speed of the spaceship:
\[ \text{Speed} = \frac{\text{Distance}}{\text{Time}} = \frac{386,400 \text{ km}}{3 \text{ days}} \]
To express speed in km per day:
\[ \text{Speed} = \frac{386,400 \text{ km}}{3} \approx 128,800 \text{ km/day} \]
Next, we find the distance to Mars at its closest approach, which is about 140 times the distance to the moon:
\[ \text{Distance to Mars} \approx 140 \times 386,400 \text{ km} = 54,096,000 \text{ km} \]
Now, we can calculate the time it would take to reach Mars at the same speed:
\[ \text{Time to Mars} = \frac{\text{Distance}}{\text{Speed}} = \frac{54,096,000 \text{ km}}{128,800 \text{ km/day}} \approx 420 \text{ days} \]
To convert days into years:
\[ 420 \text{ days} \approx \frac{420}{365} \approx 1.15 \text{ years} \]
Thus, based on this calculation, the closest approximation from the given options is:
about 1 year.