\text { 4. (10pts) Given } \omega_{2}=10 \mathrm{rad} / \mathrm{s} \text { and } \alpha_{2}=20 \mathrm{rad} / \mathrm{s}^{2}, V_{c}=10 \mathrm{in} / \mathrm{s}, \theta_{5}=15^{\circ} \text { and } \alpha_{6}=12 \mathrm{rad} /

\mathrm{s}^{2}, \text { calculate the acceleration of point B relative to point C. }