If \( \bar{a} = \bar{i} - \bar{j} + 3\bar{k} \), \( \bar{c} = -\bar{k} \) are position vectors of two points and \( \bar{b} = 2\bar{i} - \bar{j} + \lambda \bar{k} \),
\( \bar{d} = \bar{i} + \bar{j} - \bar{k} \) are two vectors, then the lines \( r = \bar{a} + t \bar{b} \), \( r = \bar{c} + s \bar{d} \) are: