The variable blocks allow you to create variables and use them in a program. Variables can store numbers or strings. Scratch supports both global and object-specific variables.

given the options, i would say your best bet is c. the modem supports up to 56 kbps, which is too low for video streaming. dial up modems use actual phone lines, which only can go up to 56 kbps as that's more than sufficient for traditional phone calls. this is also the reason why when a dial-up modem connects, you hear all those sounds. it's literally using the phone line to establish a connection.

the file button then you go to insert tab and click insert hyperlink.

that without the operating systems you would have to control and synchronize computer hardware.