Answer:
Here we assume that m and n are parallel.
Then the true statements are:
m∠2 = 20°.
You can see that the same ray cuts the two parallel lines, in one the angle formed in the left side is 20°, then the same must happen for the other line, then the measure of angle 2 is equal to 20°.
m∠3 = 100°,
We will have that:
m∠2 + m∠3 + m∠4 = 180°.
We know that m∠2 = 20°.
And if you look at m∠4, you can see that the same ray that defines it, also defines a 60° angle in the line n, then m∠4 = 60°.
then we have:
20° + m∠3 + 60° = 180°
m∠3 = 180° - 60° - 20° = 100°.
m∠2 + m∠4 = 80°.
This can be proved using the same reasoning as above.