if you can do the questions 1, 3 and 4 with coding and comments at every line
question 2 no need to code, it's about redesign, don't know how to explain but please read the attachment
21 freelancers are bidding on average $131 for this job
I read your details . Your project is very interesting. If you work with me, it will be very reasonable. Looking forward hearing from you. Best Regards. Thank.