Suppose two asteroids strike head on. Asteroid A $\left(m_{\mathrm{A}}=7.5 \times 10^{12} \mathrm{kg}\right)$ has velocity 3.3 $\mathrm{km} / \mathrm{s}$ before the collision, and asteroid $\quad \mathrm{B} \quad\left(m_{\mathrm{B}}=1.45 \times 10^{13} \mathrm{kg}\right)$ has velocity 1.4 $\mathrm{km} / \mathrm{s}$ before the collision in the opposite direction. If the asteroids stick together, what is the velocity (magnitude and direction) of the new asteroid after the collision?