A $0\mathrm{.}625$ in$.$ thick rectangular alloy bar is subjected to a tensile load P by pins at A and B as shown. The

width of the bar is $w=2\mathrm{.}00$ in$.$ Strain gages bonded to the specimen measure the following strains in the $x$

and y directions: ${}_x=1,020$ and ${}_y=-310.$

$($a$)$ Determine Poisson's ratio for this specimen.

$($b$)$ If the elastic modulus for this specimen is $12,000$

ksi $,$ what is the value of the tensile load P applied?