The resources downloaded represent the next set of lessons after the images lesson. You can work through these and add the topic 'sound representation' to your revision list. The links that I have suggested are resources that are used in the lesson. The topics we have covered so far and therefore need to be revised are:
HARDWARE Introduction to computers, System Architecture - CPU, Cache, ALU, control unit, registers, embedded systems, additional hardware, Input and output devices, Primary storage, Secondary storage. DATA REPRESENTATION Binary to denary conversions, Denary to binary conversions, Binary to Hex, Hex to Binary, Denary to Hex, Hex to denary, Adding binary, Shifting binary, Image representation, sound representation. I will expect to see all topics visited via Test and Track where I can see your attempts and results.
https://revisecomputerscience.com/- theory resources
https://www.youtube.com/channel/UC0HzEBLlJxlrwBAHJ5S9JQg - Craig n Dave video resources
https://www.bbc.co.uk/bitesize/examspecs/znywvk7 - theory resources
https://www.testandtrack.io/ - test and track