Tennis Tonic (Pty) Ltd manufactures and sells Tennis racquets. An extract from the company's marginal income statement for the month of June 2023 as well as comparative numbers is provided below: Additional information: The manufacturing equipment is leased at a flat rate per month plus an additional cost based on the number of units produced per year. Depreciation relates to equipment owned by Tennis Tonic, which is depreciated at 10% per annum on the straight-line method. a) Indicate whether the cost involved would be variable, fixed or semi variable (mixed) (3) b) Calculate the total variable cost per unit in the month of June 2023. (6) c) Calculate contribution per unit. (2) d) Calculate break-even point in units. (4)