To penetrate armor, a projectile's point concentrates force in a small area, creating a stress large enough that the armor fails. a species of jellyfish launches a pointed needle that can penetrate the hard shell of a crustacean. the rapid deceleration on impact creates a 32 μn force on the tip, which has a very small 15 nm radius.

4.527×10^{10} N/m^2

Explanation:

Assuming that the resulting stress is asked in the question in N/m^2

The stress is given by the expression

σ = F/A

F= 32μN  and A, Area= πr^2

r,  radius = 15 nm

Putting values we get

= 4.527×10^{10} N/m^2

hence the resulting stress is  4.527×10^{10} N/m^2

do you have a formula possibly

there are no contact forces mentioned on the list of choices that you've provided.