I'm having trouble calculating total cost.

The question is: Calculate the total cost for next February when 1,300 tons are expected to be extracted. I understand that trucking and hauling will be 144,970, and I also add 20,000 for depreciation, im not sure about the other costs and how to add.

Antioch Extraction, which mines ore in Montana, uses a calendar year for both financial-reporting and tax purposes. The following selected costs were incurred in December, the low point of activity, when 1,000 tons of ore were extracted:

Straight-line depreciation	$	20,000
Charitable contributions*		5,000
Mining labor/fringe benefits		135,000
Royalties		145,000
Trucking and hauling		144,970

*Incurred only in December.

Peak activity of 2,300 tons occurred in June, resulting in mining labor/fringe benefit costs of $310,500, royalties of $301,000, and trucking and hauling outlays of $174,970. The trucking and hauling outlays exhibit the following behavior:

Less than 1,000 tons	$	129,970
From 1,0001,499 tons		144,970
From 1,5001,999 tons		159,970
From 2,0002,499 tons		174,970

Antioch uses the high-low method to analyze costs.

Required:

1. Classify the five costs listed in terms of their behavior: variable, step-variable, committed fixed, discretionary fixed, step-fixed, or semivariable.

2. Calculate the total cost for next February when 1,300 tons are expected to be extracted.

3-a. Is hauling 1,000 tons with respect to Antiochs trucking/hauling cost behavior cost-effective?

3-b. Given the current scenario at what number of tons can cost-effectiveness be achieved?

4. Distinguish between committed and discretionary fixed costs. If Antioch were to experience severe economic difficulties, which of the two types of fixed costs should management try to cut?

5. Speculate as to why the companys charitable contribution cost arises only in December.