It is desired to increase the flow rate by $100\%$ in a pipeline with a fully rough turbulent flow. Which of the following changes should be made to the pipe length

and$/$or diameter to keep the pressure drop in the pipeline constant? Assume that there is no fasteners in the pipeline that would cause minor losses and that the

flow is fully rough turbulent after the changes made. Assume that fluid is incompressible.

The pipe length should be reduced by $50\%$ while the pipe diameter should remain constant

The pipe length should be kept constant and the diameter should be increased by $100\%$ at the same time.

The pipe length should be increased by $20\%$ and the pipe diameter should be reduced by $15\%$ at the same time.

The pipe length should be reduced by $50\%$ and the pipe diameter should be increased by $15\%$ at the same time.

The pipe length should be reduced by $20\%$ and the pipe diameter should be increased by $45\%$ at the same time.