Answer
The magnetic force is $4.4 \times 10^{-14}~N$ and this force is directed out of the page.
Work Step by Step
We can find the magnetic force:
$F = q~v\times B$
$F = (-1.6\times 10^{-19}~C)(8.0\times 10^5~m/s)(0.40~T)~sin~120^{\circ}$
$F = -4.4 \times 10^{-14}~N$
By the right hand rule, $v \times B$ would be directed into the page if the charge was positive. However, the negative charge results in a force directed out of the page.
The magnetic force is $4.4 \times 10^{-14}~N$ and this force is directed out of the page.
