Two horizontal forces act on a $9\mathrm{.}8$ kg chopping block that can slide over a frictionless kitchen counter, which lies in an xy plane. One force is vec$(F{)}_1=(8\mathrm{.}0N)hat(i)+(8\mathrm{.}6N)hat(j).$ Find the acceleration of the chopping block in unit$-$vector notation when the other force is $($a$)$ vec$(F{)}_2=(-8\mathrm{.}0N)hat(i)+(-8\mathrm{.}6N)hat(j),($b$)$ vec$(F{)}_2=(-8\mathrm{.}0N)hat(i)+(8\mathrm{.}6N)hat(j),$ and $($c$)$ vec$(F{)}_2=(8\mathrm{.}0N)hat(i)+(-8\mathrm{.}6N)hat(j).$

$($a$)$ Number $$ hat$(i)+$ hat$(j)$ Units $$ :$\text{'}$

$($b$)$ Number $$ hat$(i)+$ hat$(j)$ Units $$

$($c$)$ Number $$ hat$(i)+$ hat$(j)$ Units $$