Explanation

I am a teacher in a college. Recently my principal has sent an explanation letter to me asking me to explain my position for my poor result. I have written a portion of it, i want you to have a look at it and find out any mistake. It would be very kind of you if you could please give me some suggestions in this regard.
thank you.

Subject: Explanation
Dear Sir,
This is in response to your letter no ________ dated___________ subject captioned as “Explanation”. Before I plunge into my core purpose I would like to request you to kindly recalculate my result of the class in question because as per my calculation it should be 35%, whereas you have shown it 20%.
Having said that I would like to explain my position in the following points:
1) The overall result of the class in question, i.e. 1st year pre-medical, is 16%. Whereas the specific result of botany is 35%. This implies that more than 50% of those students who have failed in other subjects have passed the subject of botany. Therefore, I must say that the specific result of botany is “the least worst” or the best among the worst and hence acceptable.
2) Being an educationist I strongly believe that better result does not solely depend on better teaching. There are a number of other factors involved like parents’ interest, examination system, paper setting & checking, conceptual level & attitude of the students, family environment, and above all personal efforts and interest of the students. Then there are individual differences among the students. The question is that I was equally audible and visible to all the 46 students, then why some of them got through while some did not. Had there been any problem in me or my teaching, then how 35% students got through, while --%got above 60% marks. Therefore, holding me responsible for the failure of some students is tantamount to saying that these students had the best of everything except their teacher. I believe this is unjustifiable, unreasonable and unscientific approach.
3) I hope you have seen the recent result of BSc part I. I have no intention of boasting but this result speaks volume of my caliber, competence and teaching. Not only my pass percentage is 100% but I have also embellished the result of the college as my student,__________, has secured a distinction (3rd position) in the University Of Swabi. However, it is a cruel irony that instead of receiving a pat on the shoulder, I am handed over a letter to explain my position.
....to be continued....