<span>C. Mao Zedong
Hope this helps!~</span>
Answer:
mass of the fish is 8.11 kg
Explanation:
As we know that the frequency of oscillation of spring block system is given as

here we know that the reading of scale varies from 0 to 155 N from length varies from x = 0 to x = 10 cm
Now we have


so now we have


so mass of the fish is 8.11 kg
Answer:

Explanation:
Assuming the we have to find ratio maximum forces on the mass in each case
we know that in a spring mass system
F= Kx
K= spring constant
x= spring displacement
Case 1:

case 2:

therefore, 

Answer:
1375J
Explanation:
The gravitational potential/potential energy of the at the top of the tree which is the energy by virtue of its position.
P.E = mgh
mass = m
Acceleration due to gravity = g
height = h
At the top of the tree, the value of h (height) is high resulting in the gravitational potential. When the cat lands on the ground, the value of h is zero, the the gravitational potential would be zero and all the potential energy have been converted to other forms of energy.
Therefore, the total gravitational potential store is equal to the maximum amount of energy that can be transferred which is equal to 1375J.