If an Interstellar Cloud Having a Diameter of 10¹⁶ M

Multiple Choice

If an interstellar cloud having a diameter of 10¹⁶ m and a rotation period of a million years were to collapse to form a sphere that had the diameter of our Solar System, approximately 40 AU, what would its rotation period be? Assume the cloud's total mass and angular momentum did not change.

A) 1 million years
B) 600 years
C) 1 year
D) 6 years
E) 4 months