1. The direction ratios are 2, 5, – 3 and – 1, 8, 4.
2. The given lines are \(\bar r\) = (2i + j – 3k) + λ(2i + 5j – 3k)
i.e. \(\bar r\) = \(\bar a_1\)+λ\(\bar b_1\),
where \(\bar a_1\) = 2i + j – 3k) + λ(2i + 5j – 3k)
and \(\bar r\)=(-i + 4j + 5k) + µ(-i + 8j + 4k)

3. cosθ
