Which of the following statements is true?

The super$-$variable costing net operating income period can be computed by multiplying the number of units sold by the gross margin per unit.

All differences between super$-$variable costing and variable costing net operating income are explained by the accounting for manufacturing overhead costs.

Super$-$variable costing is a costing method that treats direct labor and manufacturing overhead costs as product costs.

Multiple Choice

Only statement $1$ is true.

Only statement $2$ is true.

Only statement $3$ is true.

None of the statements are true.