Answer:
Decrease
No change
Explanation:
As we know that
Contribution margin ratio = [(Sales - Variable Costs) ÷ (Sales) ]
Now in the case when the selling price and the variable cost would decreased by 7% so the sales and variable cost would decreased by the similar amount so there is no change in the contribution margin ratio
Also
Contribution Margin per Unit = Sales revenue per Unit - Variable Expenses per unit
Now if the selling price and the variable cost would decreased by 7% so the contribution margin would also decrease