Are these sentences correctly used in formal letters?

[thincat]

Hi everyone,

I am writing a formal letter to a lecturer. I do not know if the following sentences are correctly and politely used. Can anyone give me some feedback?

1. As I will not be back until the end of this month, may I write to ask for lecture notes of the lessons to come. (Should I use a "." or a "?"?)

2. As I will not be back until the end of this month, I write in hope that you could kindly send me lecture notes of the lessons to come.

3. As I will not be back until the end of this month, may I politely ask for you sending me lecture notes of the lessons to come.

Thank you!

 

[emsr2d2]

As I will be away until the end of the month, I would be very grateful if you would send me the lecture notes for the lectures I will miss. Thank you.