Answer:
(i) W = 8.918 N
(ii) 
(iii) d = 9.1 cm
Explanation:
Part a)
As we know that weight of cube is given as


here we know that



now the mass of the ice cube is given as

now weight is given as

Part b)
Weight of the liquid displaced must be equal to weight of the ice cube
Because as we know that force of buoyancy = weight of the of the liquid displaced

So here volume displaced is given as



Part c)
Let the cube is submerged by distance "d" inside water
So here displaced water weight is given as



so it is submerged by d = 9.1 cm inside water
That certain change from that ecosystem will require 50 years or longer because big ecosystems need a long time to restablize the living ecosystem.
Answer:
Upthrust = 20 N
Explanation:
The question says that "A body weighs 100N in air and 80N when submerged in water. Calculate the upthrust acting on the body
?"
Upthrust is defined as the force when a body is submerged in liquid, then liquid applies a force on it.
ATQ,
Weight of body in air is 100 N
Weight of body in water is 80 N
Upthrust is equal to the weight of body in air minus weight of body in water.
Upthrust = 100 N - 80 N
Upthrust = 20 N
So, 20 N of upthrust is acting on the body.
Answer:
The motion of an object is accelerated when its speed increases.