The Break-Even Analyzer

Calculate the break-even point for this business or product and show me
the sensitivities.

Price per unit: [AMOUNT]
Variable cost per unit: [AMOUNT]
Total fixed costs: [AMOUNT]
Any target profit: [AMOUNT OR NONE]

Provide:
1. Contribution margin per unit and as a %
2. Break-even in units and in revenue
3. Units/revenue needed to hit the target profit
4. A sensitivity table: break-even if price, variable cost, or fixed cost
   each move ±10%
5. The margin of safety if current volume is [CURRENT VOLUME]

Show every formula and number, and tell me which single variable the
break-even is most sensitive to.