I've answered the question. Can someone check if I got it right, please?

The cost that varies and direct proportion two changes in activity level, but remain constant on a per-unit basis =

variable cost

the range of activity over which the company expects to operate during the year=

relevant range

the level of activity at which total revenues equal the total cost =

break-even point

the percentage of each dollar of sales that is available to apply to fix cost and contribute to net income =

contribution margin ratio

the cost that contained both a variable and a fixed cost element =

maxed cost

sales variables cost equals =

contribution margin

an internal statement that classifies cost as fixed or variable and shows the contribution margin in the body of the statement =

cost volume profit income

the cushion that management has, allowing it to break even if expected sales fell to materialize =

margin of safety

costs that remain the same in total regardless of changes in the activity level but vary on a per-unit basis =

fixed costs

the amount of revenue remaining poor unit after deducting variable costs =

contribution margin per unit