The Cap Plate At $B$ Initial Pipe Diameters and Thicknesses Are

$\text { A pipe } \left( E = 110 \mathrm { GPa } \text { ) carries a load } P _ { 1 } = 120 \mathrm { kN } \text { at } A \text { and a uniformly distributed load } P _ { 2 } = 100 \mathrm { kN } \right. \text { on }$ the cap plate at $B$ . Initial pipe diameters and thicknesses are $d _ { A B } = 38 \mathrm {~mm} , t _ { A B } = 12 \mathrm {~mm} , d _ { B C } = 70 \mathrm {~mm}$ , and $t _ { B C } = 10 \mathrm {~mm}$ . Under loads $P _ { 1 }$ and $P _ { 2 }$ , wall thickness $t _ { B C }$ increases by $0.0036 \mathrm {~mm}$ . Poisson's ratio $v$ for the pipe material is approximately:

A) $0.27$
B) $0.30$
C) $0.31$
D) $0.34$