$\mathrm{}$A small block slides down a frictionless track whose shape is described by y $=($x$^2)/$d for x$<0$ and by y $=-($x$^2)/$d for x$>0.$ The value of d is $4\mathrm{.}64$ m$,$ and x and y are measured in meters as usual. Suppose the block starts from rest on the track, at x $=-2\mathrm{.}65$ m$.$ What will the block s speed be when it reaches x $=0?$