🔍 Key Concepts

• Meaning of ARPA in marine navigation • Purpose of ARPA radar on ships • Difference between a navigational aid and an organization or job title

💭 Think About

• Which option actually describes something a radar system does to targets on the screen? • Which options sound more like names of organizations or job roles rather than equipment functions? • In navigation, does ARPA mainly handle plotting, positioning angles, or people who program radar?

✅ Before You Answer

• Confirm that ARPA refers to a function of the radar, not a professional association or job title. • Check which word best fits what the system does with multiple targets: plotting, positioning angle, or programming. • Remember that marine ARPA systems automatically track and predict other vessels’ movements as a collision-avoidance aid.