Last will of Yaa’qoob; Scripture of Ibraaheem in the Qur’aan; country with largest Muslim population and how they came to Islam

1) What was the last will of Prophet
Jacob (Yacoub) (PBUH) for his children before his death?. Where do you
find this in the Holy Quran?

2)The
scripture revealed to Prophet Ibrahim (PBUH) is lost but it is mentioned
in the Holy Quran in different chapters? Give two references from two
chapters in the Holy Quran mentioning this scripture.?

3)Which Country has the highest muslim
population? How did the people of that country become muslims?.

Praise be to Allaah. 

1.                
The Qur’aan indicates that Ya’qoob gave final instructions
to his sons before he died. “… he
said unto his sons, ‘What will you worship after me?’ They said, ‘We
shall worship your Ilaah (God — Allaah) the Ilaah (God) of your fathers,
Ibraaheem (Abraham), Ismaa‘eel (Ishmael), Ishaaq (Isaac), One Ilaah
(God), and to Him we submit (in Islam).’” [al-Baqarah 2:133 –
interpretation of the meaning].

2.                
The scripture of Ibraaheem is mentioned in Soorat
al-A’laa 87:19 (interpretation of the meaning): “The
Scriptures of Ibraaheem (Abraham) and Moosa (Moses)”; and in Soorat
al-Najm 53:36-37 (interpretation of the meaning): “Or
is he not informed with what is in the Pages (Scripture) of Moosa (Moses), And
of Ibraaheem (Abraham) who fulfilled (or conveyed) all that (Allaah
ordered him to do or convey).”

3.                
The country with the
largest Muslim population in Africa is Nigeria, and in Asia, Indonesia.
The Indonesians became Muslim through contact with Muslim traders from
Hadramawt as is well known. Perhaps this is what the questioner wanted to
know, even though the question is not quite clear.