PLEASE ANSWER ASAPPPPPPP!!!!!!!!!!!!!!!!

A business makes and sells a single product, which sells for $15 per unit and which has a unit variable cost of $7. Fixed costs are expected to be $500,000 for the next year. Required: (a) What is the break-even point in sales revenue? (b) What is the break-even point in units? (c) What would be the break-even point if fixed costs went up to $640,000? (d) What would be the break-even point if fixed costs were $500,000 but unit variable costs went up to $10? (20 marks)