Since the triangles \( \triangle GHI \) and \( \triangle LJK \) are similar (\( \triangle GHI \sim \triangle LJK \)), the corresponding angles of the triangles are equal.
Given:
- \( m\angle G = 30^\circ \)
- \( m\angle H = 80^\circ \)
- \( m\angle I = 70^\circ \)
Since the triangles are similar, this means:
- \( m\angle L = m\angle G = 30^\circ \)
- \( m\angle J = m\angle H = 80^\circ \)
- \( m\angle K = m\angle I = 70^\circ \)
Thus, the measures of the angles are:
- \( m\angle J = 80^\circ \)
- \( m\angle K = 70^\circ \)
- \( m\angle L = 30^\circ \)