Each term is half of the previous one, so the common ratio is 1/2. Then to get from the first term to the nth term, you have to take n - 1 steps, multiplying by 1/2 each time and by 6000 to account for the first term.
The answer is B. 75 because 105 plus 75 equals 180 degrees...... I used to work on this when I was in 6th grade so it is easy to me hope that helped i tried my best hope you get a 100 hundred as your grade