Can someone help me with my computer architecture homework?!? Im lost. Thanks

1. In order to perform a disk or network access, it is typically necessary for a user to have the operating system communicate with the disk or network controllers. Suppose that in a particular 500 MHz computer, it takes 1,000 cycles to trap to the OS. In addition, it takes 8 ms for the Os to perform a disk access, or 4 ms for the OS to perform a network access. (8+4- 12 points) (a) In a disk access, what percentage of the delay time is spent in trapping to the OS? How about in a network access? (b) Suppose that we can somehow reduce the time for the OS to communicate with the network by 40%. The trap time is unchanged. By what percentage can we reduce the total time for a network access