DEF Corporation has provided the following data for its production costs:

Month	Units Produced	Total Cost G	Cost per Unit G	Total Cost H	Cost per Unit H	Total Cost I	Cost per Unit I
1	1,800	$7,200		$9,000		$5,400
2	3,600	$7,200		$18,000		$10,800
3	5,400	$7,200		$27,000		$16,200

Requirements:a. Calculate the cost per unit for each cost. b. Classify each cost as fixed, variable, or mixed and justify your classification. c. Describe the influence of variable costs on operating income. d. Explain the significance of fixed costs in financial stability.