Write down the magnitude of each of the following vectors: A. $\vec{a}=\hat{i}+2 \hat{j}+5 \hat{k}$ B. $\vec{b}=5 \hat{i}-4 \hat{j}-3 \hat{k}$ C. $\overrightarrow{\mathrm{c}}=\left(\frac{1}{\sqrt{3}} \hat{\mathrm{i}}-\frac{1}{\sqrt{3}} \hat{\mathrm{j}}+\frac{1}{\sqrt{3}} \hat{\mathrm{k}}\right)$ D. $\vec{d}=(\sqrt{2} \hat{i}+\sqrt{3} \hat{j}-\sqrt{5} \hat{k})$