Exam today

Hi Dear Tutor, I have a question.
Today I did well in section A.I did well section b’s 1st long question but i did not perform well in section b’s questions
First reason.
Question related to trade receivable such as factoring and early settlement discount seem to be confusing.
I were always solving these questions very well but this time i became stuck.
I remember that the question says that the cost to trade receivable under settlement option and another question said that the same thing under factoring.does it mean only calculating cost such as discount cost,admin cost and so on.
I could not solve this question due to confusing trade receivable days and current trade receivables figures showen below

trade receivable-x
bank overdraft financing charge on receivablex
bad debt-x
total -x
do we take in this case total amount or only trade receivable only?

Section c i did well in NPV calculation which is 12 marks and only mistake i did I wrongly added working capital difference over 0 year but it had to be first year’s inflated figure not figure the difference.

3 mark question fixed cost sensetivity and due to my wrong NPv result it affects my second calculation

5 marks it was about discus NPv advantages over Irr and i discussed it.

Another long question 11 weighted average cost of capital 3 mark relative cost of source of finance 6 marks capm and dgm equity calculation discussion
i performed well in 6 mark and 3 marks question.

11 marks question excell was not working as I wanted.I see th4 question it is tooooo easy i can destroy it but I became sad.
if it was paper based my mark would be at least 80.

if i pass I will.score 50 55 but i do not deserve it.