Show steps on how to choose repeating variables in buckingham pi theorem.

Buckingham π theorem states that an equation involving a certain number 'n' of variables which are expressible in terms of 'k' independent fundamental physical quantities can be expressed in terms of dimensionless parameters.
p = n - k 
Keeping the statement of Buckingham Pi Theorem,
We can proceed as follows:
Please see the attachments.I hope it helped

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