The problem with some of the content being cut off in Lecture 4 seems to be because the editing was done to force the high-resolution screen to fit the mobile environment, which had the opposite effect. The problem with the lecture audio quality is that the audio recording was recorded too low, so when editing was done by amplifying it, there was noise. Currently, we have resolved the technical issues and re-recorded and uploaded Lectures 4 and 5. We will continue to improve the other lectures by re-recording and editing them.