Please help answer question 3(b). I need more specific examples.

3. ABC's income statement is as follows: 2019 2020 Sales (units) 2,600 3,500 Sales revenue $ 130,000 $ 175,000 Total expenses 110,000 128,000 Net income $ 20,000 $ 47,000 a. Use the high-low method to estimate variable and fixed costs for 2020. (Use 2019 as the low case and 2020 as the high case). Total Variable Costs = $70,000 Total Fixed Costs = $58,000 *Please see notes b. What assumptions did you make in answering the previous question? In answering the previous question, I assumed that the cost is a mixed cost (that is composed of variable and fixed cost). Also, I assumed that both data are within the relevant range and its cost behavior is that it is linear