An airplane flight from Houston, Texas to Rome, Italy is 5,686 miles. Estimate the distance between the two cities as the product of a single digit number times a power of 10.
5 x 10^(4)
6 x 10^(3)
6 x 10^(4)
5 x 10^(3)
5 x 10^(4)
6 x 10^(3)
6 x 10^(4)
5 x 10^(3)