Ok I figured it out and hope it’s right
So the first object moving right at 5m/s
The second one moves left at 4m/s
If we multiply 2kg (5m/s) =10 kg/m/s
Same thing with the second one 1kg(4m/s)=4kg/m/s
We got two speeds and if we add them together we get 14 but I’m not sure about the units
So the answer would be A) 14m/s