User programs interact with the kernel through a set of standard (71) . They request services to be provided by the kernel. Such services would include accessing a file: open close, read, write, link, or execute a file; starting or (72) accounting records; changing ownership of a file or (73) ; changing to a new directory; creating, (74) , or killing a process; enabling access to hardware devices; and setting limits on system resources. Unix is a multi -user, multi -tasking operating system. You can have many users logged into a system simultaneously, each running many programs. It’s the kernel’s job to keep each process and user separate and to regulate access to (75) , including cpu, memory, disk and other L/O devices.

A．system hardware

B．system software

C．keyboard

D．operation system

下列收入在“营业外收入”账户中核算的内容有( )。

A．对外转让无形资产使用权

B．捐赠收入

C．购买国债取得的利息

D．非流动资产处置利得