A strain gage is installed in the longitudinal direction on the surface of an aluminum beverage can

Question:

A strain gage is installed in the longitudinal direction on the surface of an aluminum beverage can (see figure). The radius-to-thickness ratio of the can is 200. When the lid of the can is popped open, the strain changes by (0 = 170 ( 10-6.
What was the internal pressure p in the can? (Assume E = 10 ( 106 psi and v = 0.33.)