When performing sales mix analysis, which one of the following is true: O a. Making changes to the sales mix will likely cause no change in the breakeven point O b. Shifting the sales mix to the product with a lower contribution margin will likely increase the overall contribution margin O c The sales mix is usually assumed to change. Od Producing and selling more units of the product with a higher contribution margin would likely decrease the breakeven point Oe. Normally the calculation of the breakeven point for multiproduct is much simpler than that for a single product