Answer: An 8 kg book at a height of 3 m has the most gravitational potential energy.
Explanation:
Gravitational potential energy is the product of mass of object, height of object and gravitational field.
So, formula to calculate gravitational potential energy is as follows.
U = mgh
where,
m = mass of object
g = gravitational field = 
h = height of object
(A) m = 5 kg and h = 2m
Therefore, its gravitational potential energy is calculated as follows.

(B) m = 8 kg and h = 2 m
Therefore, its gravitational potential energy is calculated as follows.

(C) m = 8 kg and h = 3 m
Therefore, its gravitational potential energy is calculated as follows.

(D) m = 5 kg and h = 3 m
Therefore, its gravitational potential energy is calculated as follows.

Thus, we can conclude that an 8 kg book at a height of 3 m has the most gravitational potential energy.
Answer:
9(3x-2y)
Explanation:
27x-18y, the common factor here is 9
9(3x-2y)
Answer:
i. 15.6 m/s
ii. I = 1.44 KNs
Explanation:
The impulse, I, on a body is the product of force applied on it and the time it acts.
i.e I = F x t
Impulse is sometimes expressed as the change in momentum of a body. It is measured in Ns.
i. mass, m, of the player = 92 kg
initial velocity of the player, u = 9.4 m/s
final velocity of the player, v = 6.2 m/s
Since he bounces back on hitting the pole, then the sign of initial and final velocities are of opposite sign.
So that,
change in velocity of the player = final velocity - initial velocity
= 6.2 - (-9.4)
= 6.2 + 9.4
= 15.6 m/s
change in velocity of the player is 15.6 m/s
ii. Impulse, I = m(v - u)
= 92 x 15.6
= 1435.2
Impulse on the player is 1.44 KNs.
Answer:
It absorbs all the wavelengths of visual light that fall on it and no light is reflected into the eye from that object.
Hope this helps