Let a̅ = 2m̅ + n̅ and b̅ = m̅ - 2n̅ be the adjacent sides of a parallelogram, where m̅ and n̅ are unit vectors inclined at an angle of 60°. The lengths of the diagonals of parallelogram are:
1
\(\sqrt{5},\sqrt{5}\)
2
1, \(\sqrt{3}\)
3
\(\sqrt{7}, \sqrt{13}\)
4
\(\sqrt{2}, \sqrt{17}\)