Answer:
In waves distance is measured by wave length and time is measured by frequency or period.
velocity ratio=wave length multiply by frequency.
HENCE, if the same wave travels for 2 econds its frequency will be 2Hz.
Explanation:
I believe it’s 1 aka A part of it is reflected as Ray 2
If the hockey player is going at -3.1m/s this automatically tells you have to divide the 13m/s by the time speed of the acceleration do to the velocity change, and time so the answer would be 4.19seconds