Answer:
5kgm
Explanation:
convert cm to m and g to kg
250/1000=0.25kg
5/1000=0.05m
then find the density
density=mass/volume
=0.25kg/0.05m
=5kgm
Answer:2155 J
Explanation:
Given
Change in Internal energy
i.e. decrease in Internal Energy
Heat added to system 
According First law for a system



Thus 2155 J of work is done by system
To develop this problem it is necessary to apply the equations concerning Bernoulli's law of conservation of flow.
From Bernoulli it is possible to express the change in pressure as

Where,
Velocity
Density
g = Gravitational acceleration
h = Height
From the given values the change of flow is given as

Therefore between the two states we have to



The flow rate will have changed to 54.77 % of its original value.
Explanation:
The answer is in the pic above