Listen The following costs appear in Malgorzata Company's flexible budget at an activity level of 15.000 machine-hours: Cost A $7,800 $18,000 Cost B The relevant range of activity is from 12.000 to 18.000 machine-hours. What would be the total flexible budget amounts at an activity level of 18,000 machine hours if Cost A is a fixed cost and Cost B is a variable cost? Cost A $7,800 and Cost B $18,000. Cost A $9,360 and Cost B $25,920 Cost A $9,360 and Cost B $18,000. Cost A $7,800 and Cost B $25,920