🔍 Key Concepts

• Submarine emergency signals used to warn surface vessels of their intentions • The meaning of a yellow signal fired from a submarine versus red or other colors • The difference between distress and routine surfacing/position changes for submarines

💭 Think About

• Think about why a submarine would send a high, parachute‑type yellow signal visible from far away—what are they trying to warn nearby ships about? • Which of the options describes a situation that could most endanger surface vessels if they are not alerted in advance? • Compare which choices describe an emergency on the bottom versus a controlled maneuver where the submarine is changing depth.

✅ Before You Answer

• Verify which color(s) are typically associated with distress versus operational signaling. • Check which of the listed actions (surfacing, periscope depth, bottom distress) most needs a wide‑area visual warning to nearby ships. • Confirm from your study materials which specific action is indicated by a yellow parachute signal from a submarine.