The velocity$-$versus$-$time graph is shown for a particle moving along the x

$-$axis. Its initial position is x$0=$

$2\mathrm{.}8$ m

at t$0=$

$0$ s What is the particle's acceleration at t$=$

$3\mathrm{.}0$ s

$?$What is the particle's position at t$=$

$3\mathrm{.}0$ s

$?$