Answer:
Third option.
w = 100 °
Explanation:
The interior angles of a quadrilateral (4-sided polygon) add up to 360 °.
Let's call the 4 sides: upper, lower, left and right.
The left side has an inclination of 5 ° less with respect to the right side. That means that the angle between the left side and the bottom side, called x, is 5 ° less than 80 °, so x = 75 ° (80 ° - 5 °)
Knowing three of the four angles of the quadrilateral, we can calculate w which is the missing angle.
w + x + 80 ° + 105 ° = 360 °
Isolating w, we have
w = 360 ° - x - 80 ° - 105 °, where x = 75 °, then
w = 360 - 75 ° - 80 ° - 105 °
w = 100 °