A.) -540
Sum = N (first number + last number) / 2
N = count of consecutive numbers. Had the numbers included 1, then, N would have been 33. Since its range is 7 - 33 then 33 - 7 + 1= 27.
N = 27
Sum = 27 (-33 - 7) / 2
sum = 27 (-40)/2
sum = -1080 / 2
sum = -540
