Answer:
Straight angle
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You can determine if an angle is a straight angle only if it is 180 degrees. You can also draw it by drawing a straight line and drawing an arrow facing outward at each end.
3/5 of 42000 is 25200 so the amount of people who did not vote is 16800 because the beginning amount of 42000 subtracted from 25200 gives you the final answer
If that's confusing the answer is 16800 votes didn't pick the winner
It's a hexagon. A hexagon has 6 sides, so does the image provided. :)