The given list of statements and reasons why they are true can be 
presented in  a two column proof.
 
The reasons and statements are as follows;
Statement [tex]{}[/tex]                                     Reason:
1. m∠1 = m∠3 [tex]{}[/tex]                                 Given
m∠2 = m∠3 [tex]{}[/tex]                                   Given
2. m∠1 = m∠2  [tex]{}[/tex]                               Substitution property of equality
3. ∠1 and ∠2 are alternate interior angles (Definition of alternate interior angles)
4. l║m  [tex]{}[/tex]            If Alternate interior angles are equal then the lines are parallel.
Reasons:
The proof can be presented as follows;
- m∠1 = m∠3, and m∠2 = m∠3, given
- By substituting m∠3 with m∠1, we get; m∠1 = m∠2
- ∠1 and ∠2 are alternate interior angles based on their relative position relative to the common transversal and the two parallel lines
- The alternate interior angles m∠1 and m∠2 are equal, therefore, by alternate interior angles theorem, we have l║m.  
Therefore, the two column proof is presented as follows;
Statement [tex]{}[/tex]                                     Reason:
1. m∠1 = m∠3 [tex]{}[/tex]                                 Given
m∠2 = m∠3 [tex]{}[/tex]                                   Given
2. m∠1 = m∠2  [tex]{}[/tex]                               Substitution property of equality
3. ∠1 and ∠2 are alternate interior angles (Definition of alternate interior angles)
4. l║m  [tex]{}[/tex]            If Alternate interior angles are equal then the lines are parallel.
Learn more here:
https://brainly.com/question/12913028
https://brainly.com/question/14214033
https://brainly.com/question/4265265