Question $2(10$ points$)$

Steel with stiffness of $210$ GPa $,$ Poisson's ratio of $0\mathrm{.}33$ and allowable stress of $150$ MPa is bonded with aluminum having a stiffness of $70$ GPa $,$ Poisson's ratio of $0\mathrm{.}28$ and allowable stress of $100$ MPa to form a composite beam. The beam is simply supported and loaded by a uniformly distributed load of $5k\frac{N}{m}.$ Determine $($a$)$ the location of the neutral axis measured from the bottom up in milimeters $($no spaces between the numeric value and the units$)$

$($b$)$ the largest allowable span to $3$

significant digits measured in meters $($no spaces between numeric value and units$)$