Answer:
The measure of arcMN is 60°
Explanation:
All the way around the circle is 360°. Two marked arcs are 100° and 140°. AngleMON and AngleNOP are marked equal, which means that ArcMN and ArcNP are also equal. So we can write an equation:
100+140 + x+x =360
combine like terms.
240 + 2x = 360
subtract 240.
2x = 120
divide by 2
x = 60
ArcMN is 60°