Answer:
See explanation for answers
Step-by-step explanation:
Reason 1) Given from the problem statement(because it says that B is the midpoint of AC)
Reason 2) Because B is the midpoint of AC
Reason 3) Given frome the problem statement(because it says that AB/cong CD)
Reason 4) Because two lines congruent to each other have the same length
Reason 5(You didn't explain well)) BC=AB=CD, so BC=CD(Specific reason: Transitivity of equality)
And we're done!
