Darbro Corporation produces handheld calculators. The controller wants to analyze maintenance costs to determine the fixed cost portion and the variable rate. Data for the past 4 months: Maintenance Cost Machine Hours June $5,000 350 July 3,000 320 August 4,000 315 September 3,300 220 The controller performs regression analysis, with the following results: Intercept 1,000 X Variable 1 8.5 What is the fixed cost of maintenance? a $2,000 b $1,000 c $900 d $850