please clarify the new variable cost is 0.25 or 0.5

Problem 1 (25 points): Hoang Long Manufacturing is currently producing a tape holder that has variable cost of 0,75 USD/unit and a selling price of 2USD/unit. Fixed costs are 20,000 USD. Current volume is 40,000 units. The company can produce a better product by adding a new piece of equipment to the process line. This equipment represents an increase of 5,000 USD in fixed cost. The variable cost would decrease 0,25 USD/unit. Volume for the new and improved product should rise to 50,000 units. Questions: a) Should the company invest in the new equipment? b) At what volume does the equipment choice change/ c) At a volume of 15,000 units, which process should be used