下列哪项不符合胃溃疡癌变的特点 A．上腹痛的规律性消失 B．食欲减退 C．进行性贫血

Other genetic similarities suggested they all ________ a single, common ancestor about 300 years ago.

A．had

B．have had

C．have

D．had had

数字表中第6列四个数字之和所得结果对应的符号是（）

A．A

B．B

C．C

D．D

生产企业将委托加工收回的货物用于（）的，应视同销售货物计算缴纳增值税。

A.在建工程

B.职工福利设施

C.分配给投资者

D.生产应税产品

The (74) has several major components, including the system kernel, a memory management system, the file system manager, device drivers, and the system libraries.

A．application

B．information system

C．network

D．operating system

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