Compressive Stress on Punch

Q. Calculate the smallest punch diameter that can be designed for piercing sheet metal strip with the following data. Crushing strength of the punch material is $1500$ MPa. Thickness of the sheet is $2$ mm, factor of safety is $3$, shear strength of the sheet material $500$ MPa s

1. $2$ mm
2. $6$ mm
3. $8$ mm
4. $24$ mm