In this case, the one that responsible for avoiding a collision would be: <span>the operators of both boats
When the operators of each boat spot each other in a same area, they should use their siren to notify each other's position and uses communication device to determine how they should pass through to avoid collision</span>
The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. As the source of sound waves approaches a listener, the sound waves get closer together, increasing their frequency and the pitch of the sound.
I’m hope this help
Oil, grease and dry lubricants
<span>Black holes must have a mass THREE or more times the mass of the Sun.</span>