单选题：Suppose that we have a disk with the following parameters:

Suppose that we have a disk with the following parameters:
```
• 1TB in size
• 7200 RPM, Data transfer rate of 40 Mbytes/s (40 × 106 bytes/sec)
• Average seek time of 6ms
• ATA Controller with 2ms controller initiation time
• A block size of 4Kbytes (4096 bytes)
```
What is the average expected rotation time to read a random block from the disk?@[B](1)
A. 8ms
B. 4ms
C. 6ms
D. 2ms





A.8ms
B.4ms
C.6ms
D.2ms


答案：B