Answer
$(-0.34 T)\hat{z}$
Work Step by Step
We know that
$B=\frac{mg}{IL}$
We plug in the known values to obtain:
$B=\frac{(0.17)(9.81)}{(11)(0.45)}$
$B=0.34T$
Let us suppose that upward be the +y direction and +x direction towards right then by right hand rule the direction of magnetic field is into the page or along -z direction.
