The  magnitude of their resultant vector is 4.6 meters/seconds
Since we are to add the  velocity vectors in order to  find the magnitude of their resultant vector.
Hence:
 Resultant vector magnitude=5.8 meters/seconds + (1.2 meters/seconds)
Resultant vector magnitude=5.8 meters/seconds-1.2 meters/seconds
Resultant vector magnitude 4.6 meters/seconds
Inconclusion The  magnitude of their resultant vector is 4.6 meters/seconds
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