The average total cost of producing electronic calculators in a factory is $28 at the current output level of 190 units per week. If fixed cost is $860 per week, then what is the firm's variable cost? (enter answer as just a number, no commas, dollar signs, or the like)

The total cost of producing25 tons of butteris $45000. If average variable cost is $765, then what is the firm's average fixed cost? (enter answer as just a number, no commas, dollar signs, or the like)