Answer:

∠1 = 60°

Explanation:

120° and ∠1 are supplementary angles, that means if they are added, their sum will be 180°.

So, the solution will be:

180° - 120° = 60°

∠2 = 60°

Explanation:

∠1 and ∠2 are vertical angles, that means their measure is congruent.

So, if ∠1 is 60°, ∠2 will also be 60°.

∠3 = 120°

Explanation:

120° and ∠3 are vertical angles so that means they are congruent.

∠3 will also be measured 120°.

∠4 = 120°

Explanation:

120° and ∠4 are corresponding angles. It means that they are congruent.

So, ∠4 measures 120° also.

∠5 = 60°

Explanation:

∠1 and ∠5 are corresponding angles and they must be congruent. If ∠1 is 60°, then ∠5 is also 60°.

∠6 = 60°

Explanation:

∠5 and ∠6 are vertical angles so they must be equal. If ∠5 is 60°, ∠6 will also be 60°.

∠7 = 120°

Explanation:

∠4 is 120°. ∠4 and ∠7 are vertical angles so they are congruent. Therefore, ∠7 is also 120°.