$\hat{\mathbf{i}}+\hat{\mathbf{j}}+\hat{\mathbf{k}}$ বরাবর একক ভেক্টর কোনটি?

$\frac{\hat{i}+\hat{j}+\hat{k}}{\sqrt{3}}$

$\frac{\hat{\mathrm{i}}+\hat{\mathrm{j}}+\hat{\mathrm{k}}}{3}$

$\frac{\hat{i}+\hat{j}+\hat{k}}{\sqrt{5}}$

$\frac{\hat{\mathrm{i}}+\hat{\mathrm{j}}+\hat{\mathrm{k}}}{5}$