Answer:
The length of MN is 58 cm.
Step-by-step explanation:
In the given figure we can see that AM = MB
So, M is the mid point of AB.
Also, BN = NC ( Consider the given figure )
So, N is the mid point of BC.
Since M and N are the midpoints of AB and BC .
So, by mid segment theorem which sates that the segment joining the midpoints of any two sides of a triangle will be parallel to the third side of the triangle and half its length.
⇒ MN is parallel to AC
and



Thus , the length of MN is 58 cm.