2. Using least-squares regression, estimate the variable cost per rental return and the monthly fixed cost incurred to wash cars. Note: Round Fixed cost to the nearest whole dollar amount and the Variable cost per unit to 2 decimal places. Answer is complete but not entirely correct. 2. Using least-squares regression, estimate the variable cost per rental return and the monthly fixed cost incurred to wash cars. Note: Round Fixed cost to the nearest whole dollar amount and the Variable cost per unit to 2 decimal places. Answer is complete but not entirely correct