Ship $\mathrm{A}$ is sailing towards north-east with velocity) $\overrightarrow{v}=30\hat{\mathrm{i}}+50\hat{\mathrm{j}} \mathrm{km} {\mathrm{h}}^{-1}\mathrm{ }$ where $\hat{\mathrm{i}}$ points east and $\hat{\mathrm{j}},$ north. The ship $\mathrm{B}$ is at a distance of $80 \mathrm{k}\mathrm{m}$ east and $150 \mathrm{k}\mathrm{m}$ north of Ship $\mathrm{A}$ and is sailing towards the west at $10 \mathrm{k}\mathrm{m} {\mathrm{h}}^{-1}.$ $\mathrm{A}$ will be at the minimum distance from $\mathrm{B}$ in: