Part City faces the same normally distributed demand every year. Last year, Party City increased its balloon stock for new year's celebrations by 50. Consequently, the sales increased by 37. This year Party City is planning an additional increase of 50 balloons in the stock. How will the sales change this year with respect to the last year. a. Sales will decrease b. Sales will increase but by less than 37 c. Sales will increase exactly by 37 d. Sales will increase by more than 37