Rubium Micro Devices currently manufactures a subassembly for its main product. The costs per unit are as follows: Direct materials Direct labor Variable overhead Fixed overhead Total costs $50 45 36 38 $169 Crayola Technologies Inc. has contacted Rubium with an offer to sell 7,000 of the subassemblies for $145 each. Rubium will eliminate $91,000 of fixed overhead if it accepts the proposal. Should Rubium make or buy the subassemblies? What is the difference between the two alternatives? A. Make; savings = $7,000 B. Buy, savings = $56,000 OC. Buy, savings = $91,000 OD. Make; savings = $259,000