Deck: General Navigation

1. A receive a first return near the surface during the day, and a strong return at about 200 fathoms (366 meters) at night
2. B receive false echoes at a constant depth day and night
3. C have to recalibrate every couple of days due to inaccurate readings
4. D receive a strong return at about 200 fathoms (366 meters) during the day, and one nearer the surface at night

Tip: press A-D to answer