21. If you want to improve the performance of your PC, you need to upgrade the a. CPU
b. Monitor
c. Keyboard
d. Printer

When is an original work considered public domain? a. when posted via social media b. when it is posted on the internet c. when a copyright symbol is not included with the piece of work d. when explicit permission is given by the author / owner

Does read theory have answers keys ?

How to do this programming flowchart?