Can you please tell me what type of madd the word "laa" is in the beginining of sura balad.

Question
Salam, can you please tell me what type of madd the word "laa" is in the beginning of sura balad?

Answer
Wa alaikum assalaam wa rahmatullahi wa barakatuh. 
This is the Separated Allowed Medd, because the medd letter (alif) in the word "" is a separate word from the hamzah which is the first letter of the next word. 

Please see the following link for details about this type of medd:

http://www.abouttajweed.com/the-mudood-the-lengthenings-/the-mudood-lengthenings-part-6.html