If the vectors given below, the parallel vectors are,$\overline{a}=3\widehat{i}+4\widehat{j} , \overline{b}=150\widehat{i}+220\widehat{k}$ $and \overline{c}=0.6\widehat{i}+0.8\widehat{j}, \overline{d}=\widehat{i}+2\widehat{j}+3\widehat{k}$

$Given that , \overline{a}=3\widehat{i}+4\widehat{j} , \overline{b}=150\widehat{i}+220\widehat{k and \overline{c}=0.6\widehat{i}+0.8\widehat{j}, \overline{d}=\widehat{i}+2\widehat{j}+3\widehat{k}}$

To find parallel vectors we need to calculate unit vector

$unit vector of \overline{a} is$

$\overline{a}=\frac{3\hat{i}+4\hat{j}}{\sqrt{3^2+4^2}}=\frac{3}{5}\hat{i}+\frac{4}{5}\hat{j}$

$\overline{a}=0.6\hat{i}+0.8\hat{j}=\overline{c}$

$\therefore$$\overline{a}$ and $\overline{c}$ are parallel vector