Point a because point a is the highest at potential energy converting into the highest kinetic energy.
Answer:
The speed of water must be expelled at 6.06 m/s
Explanation:
Neglecting any drag effects of the surrounding water we can assume the linear momentum in this case is conserves, that is, the total initial momentum of the octopus and the water kept in it cavity should be equal to the total final linear momentum. That's known as conservation of momentum, mathematically expressed as:

with Pi the total initial momentum and Pf the final total momentum. The total momentum is the sum of the momentums of the individual objects, in our case the octopus and the mass of water that will be expelled:

with Po the momentum of the octopus and Pw the momentum of expelled water. Linear momentum is defined as mass times velocity:

Note that initially the octopus has the water in its cavity and both are at rest before it sees the predator so
:

We should find the final velocity of water if the final velocity of the octopus is 2.70 m/s, solving for
:


The minus sign indicates the velocity of the water is opposite the velocity of the octopus.
Two forces 3N and 4N act on a body in a direction due north From East, the equilibrant's angle is given by
.
<h3>What are equilibrium and resultant force?</h3>
The equilibrium force is the balanced force when the net force acting is zero and is the exact opposite of the consequent force. The resultant force is one single force replaced by numerous forces.
<h3>Briefing:</h3>
3N and 4N are the two forces pulling on a body.
The forces work along the North and the East, which are perpendicular to one another.
The resultant of the forces, which is provided by the equilibrant force,
R = √(3)²+(4)²
R = 5N
From East, the equilibrant's angle is given by

To know more about equilibrium force visit:
brainly.com/question/12582625
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