An astronomical unit is the average distance in miles from Earth to the Sun. The average distance from Earth to the Sun is about 92,960,000 miles. Which number represents an astronomical unit written in scientific notation?

a. 9.296 x 10⁴ miles
b. 9.296 x 10⁶ miles
c. 9.296 x 10⁷ miles
d. 9.296 x 10⁸ miles