Someone help and please make sure it’s right

Angle mno is s rotated 180 degrees counterclockwise about the origin to form angle m’n’o’. which statement shows the measure of angle m’n’o’?

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

Four individuals pool money together to start a new business and agree to split the profits equally. n invests $6,000, x invests $2,000, y invests $8,000 and z invests $4,000. if the profits for the first month were $100,000, y receives than if the profits were divided in proportion to how much they invested.