Represent the following sentence by a Boolean expression:
“In a battery-powered computer, the disk drive motor 1 should be on if and only if
(a) There is a disk in the drive, and
(b) The disk drive is closed, and
(c) The disk drive motor 2 is not on, and
(d) The battery low signal is not present, and
(e) The computer has started a read operation, or the computer has started a write operation.”