Given two rectangular ducts with equal flowrate, length and cross$-$sectional area, but different aspect ratios $($width$/$height$)$ of $3$ and $6.$

a$)$ Which will have the greater frictional losses? Explain your answer.

b$)$ Show me how you can solve the procedure $($step $1,$ step$2,...)$ to find the friction factors for the two aspect ratios $($width$/$height$)3$ and $6$ rectangles. And what do you need to find it$.$