If the spectrum of a signal is discrete and periodic, then the corresponding time domain signal is_____. ( ) A: continue and periodic B: continue and aperiodic C: discrete and periodic D: discrete and aperiodic

Which of the following functions can a timer in a computer system be used to achieve? A: Generate interrupt signal regularly B: Measuring the frequency of external periodic signals C: Generate periodic pulse signals D: Generate periodic sine wave

The periodic table is just a common table.

Who did firstly show the Periodic table?  (    )

The function [img=114x27]1803e256894224d.png[/img] is a periodic function.

What is the difference between the periodic and perpetual inventory systems

For publicly held companies, periodic financial reports are required by law.

From a rhetorical point of view, which kind of sentence does the following sentence belong to?If you’ve got the time, we’ve got the beer.? Loose|Periodic|Both periodic and loose|Balanced

What are the general characteristics of motion for driving links in a machine at the steady running stage? A: Periodic fluctuation B: Non-periodic fluctuation C: Keep changing between periodic and non-periodic fluctuation D: Remains constant

99. Periodic publications notifying changes in，or additions to，previously published navigational data are ________.