Problem $1(16$ points$)$

For a particular copper alloy material, the flow curve parameters are $700$ MPa for the strength coefficient and

$0\mathrm{.}35$ for the strain$-$hardening exponent. You are asked to perform a compression test on a cylindrical specimen

of this material with an initial cross$-$section area of $1,000m{m}^2$ and a height of $65$ mm $.$ Assuming uniform

deformation and volume constancy, calculate the following:

$($a$)$ The engineering strain and true strain.

$($b$)$ The load required to compress the specimen to a height of $55$ mm $.$