In abc , m b =140 and m c=10. in def , m d=30 and m f=10. which statement about the triangles is true?

In triangle ABC,  <B = 140, <C = 10
so <A = 180 - 140 - 10 = 30

In triangle DEF , <D = 30 and <F = 10
so <E = 180 - 30 - 10 = 140

Now you have
<A = <D = 30
<B = <E = 140
<C = <F = 10

Conclusion: triangle ABC is similar to triangle DEF

Answer is the last one.

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