both questions please

Pepper Company currently sells 30,000 units a month for $50 each, with a variable cost of $30 per unit, and fixed costs of $320,000. Net operating income is currently $280,000. If the price is increased to $70 per unit, and variable cost per unit and fixed costs remain the same, how many units must be sold to earn the same net operating income of $280,000? O 22,500 O 15,000 4,000 O 8,000 Bonus question. Cost behavior is best described as O determining whether a cost has been good or bad O the way in which costs change when the activity level changes O studying how people feel about costs