Septuagint and Apocrypha

Heb. 10:5 is quoted from the Septuagint version of Psalm 40:6.
Acts 7:14 says that 75 people came from Canaan into Egypt. The Massoretic text says 70, and the Septuagint says 75 which is in agreement with Gen. 46:27.
Is. 7:14 in the Septuagint says virgin while the Massoretic text says young maiden.
The earliest copies of the Septuagint (codex Alexandrinus and codex Siniaticus) from the 4th and 5th centuries contain the Apocrypha.
Clement of Rome (30-100), Polycarp (65-155), Irenaeus (120-202), Clement of Alexandria (155-217), and Origen (185-254) all quote from the Apocrypha.
The oldest manuscripts containing substantial quotes from the Massoretic text still in existence date from the 9th century. The earliest complete manuscript is from the 10th century.
The Massoretic text was copied and edited by a group of Jews called the Massoretes between the 7th and 9th centuries A.D.
The Massoretic text was decided upon by the Pharisees in the council of Jamnia in 70 A.D.