Mathspace Senior Frontend Developer interview questions

The interview was with Alvin Savoy. The first round was fairly straightforward ( questions posted below ) The second round involved creating a graph component in react and uses mouseDrag event handlers to resize the bars. No 3rd party libs were to be used. They state no more than 4 hours, and that could be fine if you've done this sort of finicky work before, but I struggled a lot and although i finished it, it was very buggy. No response. No feedback. Ghosted.