假设一个有3个盘片的硬盘，共有4个记录面，盘面有效记录区域的外直径为30cm，内直径为10cm，记录位密度为250位/mm，磁道密度为8道/mm，每磁道分16个扇区，每扇区 512字节，则该硬盘的非格式化容量和格式化容量约为(35)。

(64)

(63)

(62)

(61)

(59)

In the following essay, each blank has four choices. Choose the best answer and write down on the answer sheet.

(57)

(58)

(56)

In(66)the strength of the carrier signal is varied to represent binary 1 or 0.(67)is a system that can map a name to an address and conversely an address to an name.(68)is a three -way handshaking authentication protocol that it's packets are encapsulated in the point - to -point protocol.(69)is an approach that enables an ATM Switch to behave like a LAN switch.(70)is an guided media which is made of glass or plastic and transmits signals in the form. of light.