Answer:
electron dot diagram is the answer to your question.
Answer:

Explanation:
The volume flow rate of a fluid in a pipe is given by:

where
A is the cross-sectional area of the pipe
v is the speed of the fluid
In this problem, at the initial point we have
v = 0.84 m/s is the speed of the water
r = 0.21 m is the radius of the pipe, so the cross-sectional area is

So, the volume flow rate is

Answer:
due to production of heat through friction