Hello there, can you teach me how to do this question, thank you

Hello there,

can you teach me how to do this question,

thank you

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• Attachment 2

13]Giveu that the resistance R of a blood vessel of length l and radius r is given by R = E; where k is a constant. 1'Also given there is 5% increase in radius so new radius isr‘ = r + 5% ofr =...