Which angle is not coterminal to 120 degrees? 840,-600,-180,480?

I’m stuck on this equation, anyone got the answer?

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?

Astore is having a sale in which all items are reduced by 20 percent. including tax, jennifer paid $21 for a pair of shorts. if the sales tax is 5 percent, what was the original price of the shorts