Cathy Company used the high-low method to derive its cost formula for a mixed cost. According to the cost formula, the variable cost per unit of activity is $1 per machine hour. Total mixed cost at the high level of activity was $7,400 and at the low level of activity was $7,000. If the low level of activity was 1,200 machine hours, then the high level of activity was: O 1,800 machine hours 1,400 machine hours O 1,000 machine hours O 2,000 machine hours O 1,600 machine hours