Hagle Incorporated saw an increase in sales of $10\%$ ?last year. Selling price per unit, variable cost per unit, and total fixed costs remained constant. Determine whether the following items.

$\backslash$table$[[10\%$ ?Increase in Sales,Impact$],[$a$.$ ?Total sales,$],[$b$.$ ?Contribution margin per unit,$],[$c$.$ ?Margin of safety,$],[$d$.$ ?Breakeven point,$]]$