The initial momentum of the system can be expressed as,

The final momentum of the system can be given as,

According to conservation of momentum,

Plug in the known expressions,

Initially, the second mass move towards the first mass therefore the initial speed of second mass will be taken as negative and the recoil velocity of first mass is also taken as negative.
Plug in the known values,

Thus, the final velocity of second mass is 2.99 m/s.
Potential energy = mass x gravity x height
P.E = 4 x 9.8 x 3
P.E = 117.6 J
b..a harmless organism imitating the look of a harmful organism
Explanation:
A harmless organism imitating the look of a harmful organism is one example of mimicry that enables prey species avoid predation.
Prey are smaller and less harmful organisms often hunted by larger organisms usually carnivores.
Mimicry is a form of evolutionary adaptation process in which two organisms of the same specie or different species tends to look alike.
It is a subtle defense mechanism developed by organism over an extended period of time.
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Adaptation brainly.com/question/11105547
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