\bullet A particle with mass $1.81 \times 10^{-3} \mathrm{kg}$ and charge of $+1.22 \times 10^{-8} \mathrm{Chas},$ at a given instant, a velocity of $3.00 \times 10^{4} \mathrm{m} / \mathrm{s}$ along the $+y$ -axis, as shown in Figure $20.58 .$ What are the magnitude and direction of the particle's acceleration produced by a magnetic field of magnitude 1.25 $\mathrm{T}$ in the $x y-$ plane, directed at an angle of $45.0^{\circ}$ counterclockwise from the $+x$ -axis?