$1.$ What is the revised net operating income if unit sales increase by $19\%?$

$2.$ What is the revised net operating income if the selling price decreases by $$1\mathrm{.}40$ per unit and the number of units sold increases by $19\%?$

$3.$ What is the revised net operating income if the selling price increases by $$1\mathrm{.}40$ per unit, fixed expenses increase by $$10,000,$ and the number of units sold decreases by $3\%?$

$4.$ What is the revised net operating income if the selling price per unit increases by $20\%,$ variable expenses increase by $20$ cents per unit, and the number of units sold decreases by $8\%?$