Please help ( in computer system language 221) chapter 6

TQ.1] Describe the steps when the CPU initiates a transaction to read data from the Dynamic Random Access Memory (DRAM). Q.2] Describe the steps when the CPU initiates a transaction to write data to the DRAM. TQ.3] Explain when and why the disk controller performs Direct Memory Access (DMA) to the main memory TO.4] What is the capacity of a disk with 4 platters, 20,000 cylinders, an average of 500 sectors per track, and 1024 bytes per sector? TQ.51 Using the disk in Q4, assume its rotational rate is 9.600 revolutions per minute, and the average seek time is 8 ms. Find the average estimated access time