40. The disk drives connected to the servers in your company’s server farm are nearing the end of their useful lives. Management is considering replacing 8TB of disk capacity with SSDs. Someone is making the argument that the difference in the cost between the SSDs and traditional magnetic disks will be offset by the cost of electricity saved by the SSDs. The 800GB SSDs cost $900. The 800GB server-grade HDDs cost $300. Use the disk specifications in Figures 7.15 and 7.17 to confirm or refute this claim. Assume that both the HDD and the SSD are active 25% of the time and that the cost of electricity is $0.10 per kilowatt hour. Hint: Use the

“Read/Write” and “Idle” power requirements in Figure 7.15.