A seamless spherical shell is of 0.8 m internal diameter and 4 mm thickness. It is filled with fluid under pressure until its volume increases by 50 cubic centimeters. Determine the fluid pressure, taking E = 2 105 N/mm and Poisson's ratio = 0.3. (a) 17.77 N/mm (b) 12.38 N/mm (c) 4.56 N/mm (d) 0.355 N/mm