摄影是19世纪初,大约是()就出现科技新鲜事物,普遍认可的是,()末期。
A、10-20年代
B、15-25年代
C、19世纪30年代
D、20世纪40年代
参考答案:A, C
进行食品的沙门菌检验时,选择性分离平板上面出现了可疑菌落。
将沙门菌菌株接种在半固体琼脂平板中央,待蔓延生长后取菌落最边缘的菌苔进行玻片凝集,这是为了检查()
A.K抗原
B.F抗原
C.Vi抗原和O抗原
D.O抗原
E.H抗原
TCP/IP (71) layer protocols provide services to the application (72) running on a computer. The application layer does not define the application itself, but rather it defines (73) that applications need — like the ability to transfer a file in the case of HTTP. In short, the application layer provides an (74) between software running on a computer and the network itself. The TCP/IP application layer includes a relatively large number of protocols, with HTTP being only one of those. The TCP/IP (75) layer consists of two main protocol options — the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP).
A. application B. transport C. link D. network