Let P be the minimum pressure needed to break the skin. If a needle is pushed into the skin with force F, what is the maximum radius r the needle can have in order to be able to break the skin? Derive an analytical expression for r in terms of P and F.

answer only analytical plz .no numbers all steps included.

(B)

Studies have shown that the value of P is around 700,000Pa700,000Pa. Calculate r if the force being applied is F=100N Check that your answer makes sense in terms of units and numerical value.