Answer:

Explanation:
When two parallel lines intersect the following relationships amongst the angles hold
Corresponding angles: These are angles that are in the same position relative to the parallel lines, but on different lines. Corresponding angles are congruent. Here the pairs of corresponding angles are:
∠1 and ∠3: m∠1 = m∠3
∠2 and ∠4: m∠2 = m∠4
∠8 and ∠6 m∠8 = m∠6
∠7 and ∠5: m∠7 = m∠5
Same-side interior angles: These are angles that are inside the parallel lines, on the same side of the transversal. Same-side interior angles are supplementary, which means their measures add up to 180 degrees
∠1 and ∠8 are supplementary angles.
So m∠1 + m∠8 = 180°
Since m∠1 = 40°
m∠8 = 180° - 40° = 140°
Since ∠8 and ∠6 are corresponding angles, and m∠8 = m∠6
we have 140° = m∠6
So m∠6 = 140°
There are relationships among the other angles, just look them up