Slope of Line 1: \( m_1 = -2.5 \)
Slope of Line 2: \( m_2 = 1.4 \)
Slope of Line 3: \( m_3 = -2.5 \)
Line 1 and Line 2: Neither
Line 1 and Line 3: Parallel
Line 2 and Line 3: Neither
Thus, the final answers are:
\[
\boxed{m_1 = -2.5, \, m_2 = 1.4, \, m_3 = -2.5}
\]
\[
\boxed{\text{Line 1 and Line 2: Neither, Line 1 and Line 3: Parallel, Line 2 and Line 3: Neither}}
\]