d. Maintain constant velocity
Explanation:
A constant velocity leads to no acceleration.
Acceleration is defined as the change in velocity with time:
Acceleration = 
If there is no change in velocity i.e constant velocity.
At constant velocity, the change in velocity is 0.
If we put zero in the equation above, we will obtain an acceleration value of 0.
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Acceleration brainly.com/question/3820012
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<h2>
Kinetic energy just before hitting the floor is 324.57 J</h2>
Explanation:
Weight of volleyball player = 650 N
That is
Mass x Acceleration due to gravity = 650
Mass x 9.81 = 650
Mass = 66.26 kg
We also have equation of motion v² = u² + 2as
Initial velocity, u = 0 m/s
Acceleration, a = 9.81 m/s²
Final velocity, v = ?
Displacement, s = 0.5 m
Substituting
v² = u² + 2as
v² = 0² + 2 x 9.81 x 0.5
v = 3.13 m/s
Velocity with which he lands on ground is 3.13 m/s
We have kinetic energy = 0.5 x Mass x Velocity²
Substituting
Kinetic energy = 0.5 x 66.26 x 3.13²
Kinetic energy = 324.57 J
Kinetic energy just before hitting the floor is 324.57 J
Potential energy is the energy possessed by a body by virtue of its position or configuration . And energy is the capacity of doing work since power is work divided by time therefore change in potential energy divided by time is equal to the power of the object.
B. Flipped compared to what is in the sky
I think the correct answer from the choices listed above is the second option. For endothermic reactions, the reactants have less energy than the products. Which would mean that energy should be added to the reaction for it to proceed. Hope this answers the question.