Marcus tried to solve an equation step by step. 2.5b=5

Step 1- 2.5b 5
=
2.5 2.5

Step 2- b=3

In which step did marcus make a mistake:

A - Step 1
B- Step 2
C- Marcus did not make i mistake

*let m∠cob = 50°30’, m∠aob = 70° and m∠aoc = 20°30’. could point c be in the interior of ∠aob? why? a. point c could be the interior of aob but it is not the only case b. point c is the interior of aob c. point c is not the interior of aob d. the given is not possible for the plane geometry answer