Determine the margin of safety ratio from the following data:

Sales

$30$ per unit

Variable Cost $10$ per unit $(8$ production cost, $2$ selling and administration cost$)$

Units Sold $7,500$ units

Fixed Costs $100,000(80,000$ production costs, the remainder is selling and administration cost$)$

$75\%.$

$20\%.$

$45\%.$

$33\%.$